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Filed Pursuant to Rule 424(B)(5)
Registration No. 333-163914

The information in this preliminary prospectus supplement is not complete and may be changed. This preliminary prospectus supplement and the accompanying prospectus are not an offer to sell these securities, and we are not soliciting offers to buy these securities, in any jurisdiction where the offer or sale is not permitted.

SUBJECT TO COMPLETION, DATED AUGUST 2, 2011

PRELIMINARY PROSPECTUS SUPPLEMENT
(To Prospectus dated June 17, 2011)

$            

SL Green Realty Corp.
SL Green Operating Partnership, L.P.
Reckson Operating Partnership, L.P.

      % Senior Notes due 20    

         SL Green Realty Corp. or SL Green, SL Green Operating Partnership, L.P. or SL Green OP, and Reckson Operating Partnership, L.P. or ROP (collectively, the "co-obligors"), are jointly and severally offering $       million principal amount of        % Senior Notes due 20    at         % of the principal amount of the notes, which we refer to as the "notes."

The Co-Obligors:

•

We are engaged in the ownership, management, operation, leasing, financing and development of commercial real estate properties, principally office properties, and also own land for future development located in Manhattan, Brooklyn, Queens, Long Island, Westchester County, Connecticut and New Jersey, which collectively is also known as the New York Metropolitan area.

The Offering:

•

We intend to use the net proceeds from the sale of the notes offered hereby to repay a portion of the amount outstanding under our revolving credit facility and for general corporate purposes and/or working capital purposes, which may include investment opportunities, purchases of the indebtedness of SL Green and its subsidiaries, including SL Green OP and ROP, in the open market from time to time, and the repayment of indebtedness at the applicable maturity or put date.

The Notes:

•

Maturity: The notes will mature on                        , 20    .



•

Interest Payments: The notes will bear interest at the rate of        % per year. We will pay interest on the notes semiannually in arrears in cash on                    and                    of each year, beginning on                        , 20    .



•

Ranking: The notes will be the unsecured senior obligations of SL Green, SL Green OP and ROP and rank equally with each entity's other unsecured and senior indebtedness from time to time outstanding.



•

Optional Redemption: We may redeem the notes, in whole or from time to time in part, at the redemption price described in "Description of the Notes—Optional Redemption."



•

Denomination: The notes will be issued only in registered form in minimum denominations of $2,000 and integral multiples of $1,000 in excess thereof.



•

Listing and Public Market: The notes will not be listed on any securities exchange. Currently, no public market exists for the notes.

         Investing in our notes involves risks, which you should consider before investing. See "Risk Factors" beginning on page S-6 of this prospectus supplement, page 3 of the accompanying prospectus and the risk factors incorporated by reference herein.

         Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

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Plus accrued interest, if any, from                        , 2011 if settlement occurs after that date.

         The underwriters expect to deliver the notes to investors on or about                        , 2011 only in book-entry form through the facilities of The Depositary Trust Company, or DTC.

Joint Book-Running Managers

The date of this prospectus supplement is                        , 2011.

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Prospectus Supplement

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        You should rely only on the information contained in or incorporated by reference in this prospectus supplement, the accompanying prospectus and any related free writing prospectus we provide to you that is required to be filed with the Securities and Exchange Commission, or the SEC. Neither we nor the underwriters have authorized any other person to provide you with additional or different information. If anyone provides you with additional or different information, you should not rely on it. Neither we nor the underwriters are making an offer to sell the notes in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus supplement, the accompanying prospectus, any such free writing prospectus and the documents incorporated by reference herein and therein is accurate only as of their respective dates. Our business, financial condition, results of operations and prospects may have changed since those dates.

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ABOUT THIS PROSPECTUS SUPPLEMENT

        This document is in two parts. The first part is this prospectus supplement, which adds to and updates information contained in the accompanying prospectus as well as the documents incorporated by reference into this prospectus supplement. The second part, the accompanying prospectus, gives more general information about securities we may offer from time to time, some of which does not apply to the notes. To the extent any inconsistency or conflict exists between the information included in this prospectus supplement and the information included in the accompanying prospectus or any information incorporated by reference, the information contained in this prospectus supplement updates and supersedes such information. The information incorporated by reference into this prospectus supplement includes important business and financial information about us that is not included in, or delivered with, this prospectus supplement.

        It is important for you to read and consider all information contained in this prospectus supplement and the accompanying prospectus in making your investment decision. You should also read and consider the information contained in the documents we have referred you to in this prospectus supplement under the heading "Where You Can Find More Information; Incorporation by Reference," which supersedes the information referred to under the heading "Where You Can Find More Information; Incorporation by Reference" in the accompanying prospectus.

CAUTIONARY STATEMENT REGARDING FORWARD LOOKING STATEMENTS

        This prospectus supplement, the accompanying prospectus and the documents incorporated by reference herein include certain statements that may be deemed to be "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995 and are intended to be covered by the safe harbor provisions thereof. All statements, other than statements of historical facts, included in this prospectus supplement, the accompanying prospectus and the documents incorporated by reference herein that address activities, events or developments that we expect, believe or anticipate will or may occur in the future, including such matters as future capital expenditures, dividends and acquisitions (including the amount and nature thereof), development trends of the real estate industry and the Manhattan, Brooklyn, Queens, Long Island, Westchester County, Connecticut, and New Jersey office markets, business strategies, expansion and growth of our operations and other similar matters, are forward-looking statements. These forward-looking statements are based on certain assumptions and analyses made by us in light of our experience and our perception of historical trends, current conditions, expected future developments and other factors we believe are appropriate.

        Forward-looking statements are not guarantees of future performance and actual results or developments may materially differ, and we caution you not to place undue reliance on such statements. Forward-looking statements are generally identifiable by the use of the words "may," "will," "should," "expect," "anticipate," "estimate," "believe," "intend," "project," "continue," or the negative of these words, or other similar words or terms.

        Forward-looking statements contained in this prospectus supplement, the accompanying prospectus and the documents incorporated by reference herein are subject to a number of risks and uncertainties which may cause our actual results, performance or achievements to be materially different from future results, performance or achievements expressed or implied by forward-looking statements made by us. These risks and uncertainties include:

•

the effect of the credit crisis on general economic, business and financial conditions, and on the New York Metropolitan area real estate market in particular;



•

dependence upon certain geographic markets;



•

risks of real estate acquisitions, dispositions and developments, including the cost of construction delays and cost overruns;

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•

risks relating to debt and preferred equity investments;



•

availability and creditworthiness of prospective tenants and borrowers;



•

bankruptcy or insolvency of a major tenant or a significant number of smaller tenants;



•

adverse changes in the real estate markets, including reduced demand for office space, increasing vacancy, and increasing availability of sublease space;



•

availability of capital (debt and equity);



•

unanticipated increases in financing and other costs, including a rise in interest rates;



•

our or our subsidiaries' ability to comply with financial covenants in our debt instruments;



•

SL Green's ability to maintain its status as a REIT for federal income tax purposes, SL Green OP's ability to satisfy the rules in order for it to qualify as a partnership for federal income tax purposes, the ability of certain of our subsidiaries to qualify as REITs and certain of our subsidiaries to qualify as taxable REIT subsidiaries for federal income tax purposes and the ability of our subsidiaries to operate effectively within the limitations imposed by these rules;



•

risks of investing through joint venture structures, including the fulfillment by our partners of their financial obligations;



•

the continuing threat of terrorist attacks, in particular in the New York Metropolitan area and on our tenants;



•

our ability to obtain adequate insurance coverage at a reasonable cost and the potential for losses in excess of our insurance coverage, including as a result of environmental contamination; and



•

legislative, regulatory and/or safety requirements adversely affecting REITs and the real estate business, including costs of compliance with the Americans with Disabilities Act, the Fair Housing Act and other similar laws and regulations.

        Other factors and risks to our business, many of which are beyond our control, are described in our filings with the SEC. We undertake no obligation to publicly update or revise any forward-looking statements, whether as a result of future events, new information or otherwise.

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SUMMARY

        The following summary highlights selected information contained or incorporated by reference in this prospectus supplement and accompanying prospectus and does not contain all of the information that may be important to you. You should carefully read this entire prospectus supplement and the accompanying prospectus, including the financial data and related notes and the documents incorporated by reference herein and therein, before making a decision to invest in the notes. Unless the context requires otherwise, the term "SL Green" refers to SL Green Realty Corp. Unless the context requires otherwise, the term "SL Green OP" refers to SL Green Operating Partnership, L.P. Unless the context requires otherwise, the term "ROP" refers to Reckson Operating Partnership, L.P. and all entities owned or controlled by Reckson Operating Partnership, L.P. Unless the context requires otherwise, the terms "we," "our," "ours," and us refers to SL Green Realty Corp., SL Green Operating Partnership, L.P. and Reckson Operating Partnership, L.P. and their respective subsidiaries on a consolidated basis.

SL Green Realty Corp.

        SL Green, a Maryland corporation, is a self-managed real estate investment trust, or REIT, with in-house capabilities in property management, acquisitions, financing, development, construction and leasing. SL Green was formed in June 1997 for the purpose of combining the commercial real estate business of S.L. Green Properties, Inc., SL Green's predecessor entity and its affiliated partnerships and entities. S.L. Green Properties, Inc., which was founded in 1980 by Stephen L. Green, the Chairman of SL Green, had been engaged in the business of owning, managing, leasing, acquiring and repositioning office properties in Manhattan. SL Green began trading on the New York Stock Exchange, or NYSE, on August 15, 1997 under the symbol "SLG."

        As of March 31, 2011, SL Green (inclusive of ROP) owned the following interests in commercial office properties in the New York Metropolitan area, primarily in midtown Manhattan. SL Green's investments in the New York Metropolitan area (inclusive of ROP) also include investments in Brooklyn, Queens, Long Island, Westchester County, Connecticut and New Jersey, which are collectively known as SL Green's Suburban assets:

        As of March 31, 2011, SL Green's Manhattan properties (inclusive of ROP) were comprised of fee ownership (23 properties), including ownership in condominium units, and leasehold ownership (seven properties). As of March 31, 2011, SL Green's Suburban properties (inclusive of ROP) were comprised of fee ownership (30 properties), and leasehold ownership (one property).

        As of March 31, 2011, SL Green (inclusive of ROP) also owned investments in nine retail properties encompassing approximately 334,782 square feet, six development properties encompassing approximately 1,277,521 square feet and three land interests. SL Green managed four office properties owned by third parties and affiliated companies encompassing approximately 1.3 million rentable square feet, as of March 31, 2011. SL Green held approximately $579.3 million of debt and preferred equity investments, as of March 31, 2011.

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SL Green Operating Partnership, L.P.

        SL Green is the sole managing general partner of SL Green OP. Substantially all of SL Green's assets are held by, and all of its operations are conducted through, SL Green OP. As of March 31, 2011, SL Green owned approximately 97.7% of the economic interests in SL Green OP and minority investors held, in the aggregate, an approximately 2.3% limited partnership interest in SL Green OP.

Reckson Operating Partnership, L.P.

        ROP is engaged in the ownership, management, operation and development of commercial real estate properties, principally office properties, and also owns land for future development located in the New York Metropolitan area. At March 31, 2011, ROP's inventory of development parcels aggregated approximately 81 acres of land in four separate parcels on which ROP can, based on estimates at March 31, 2011, develop approximately 1.1 million square feet of office space and in which ROP had invested approximately $66.4 million. In addition, as of March 31, 2011, ROP also held approximately $2.5 million of debt investments.

        ROP commenced operations on June 2, 1995. A wholly-owned subsidiary of SL Green OP is the sole general partner of ROP. SL Green OP is the sole limited partner of ROP.

        As of March 31, 2011, ROP owned the following interests in commercial office properties in the New York Metropolitan area, primarily in midtown Manhattan. ROP's investments in the New York Metropolitan area also include investments in Queens, Westchester County and Connecticut, which are collectively known as ROP's Suburban assets:

        As of March 31, 2011, ROP's Manhattan properties were comprised of fee ownership (three properties) and leasehold ownership (one property). ROP is responsible for not only collecting rent from subtenants, but also maintaining the property and paying expenses relating to the property. As of March 31, 2011, ROP's Suburban properties were comprised of fee ownership (16 properties) and leasehold ownership (one property).

Headquarters

        SL Green's, SL Green OP's and ROP's principal executive offices are located in midtown Manhattan at 420 Lexington Avenue, New York, New York 10170. We can be contacted at (212) 594-2700.

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The Offering

        The following is a brief summary of certain terms of this offering. For a more complete description of the terms of notes, see "Description of the Notes" in this prospectus supplement and "Description of Debt Securities" in the accompanying prospectus.

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RISK FACTORS

        An investment in the notes involves a high degree of risk. Before deciding to purchase any notes, you should carefully consider the risks and uncertainties set forth below and the risks and uncertainties incorporated by reference in this prospectus supplement and the accompanying prospectus, including the information included under "Risk Factors" in SL Green's Annual Report on Form 10-K for the year ended December 31, 2010, in SL Green OP's Annual Report on Form 10-K for the year ended December 31, 2010, in ROP's Annual Report on Form 10-K for the year ended December 31, 2010 and other documents that we subsequently file with the SEC.

        These risks and uncertainties are not the only ones facing us. There may be other risks that a prospective investor should consider that are relevant to that investor's own particular circumstances or generally.

Risks Related to the Offering of the Notes

Our level of indebtedness could adversely affect our operations and effectively reduce the amount of funds available for other business purposes, including our ability to make payments of principal and interest on the notes.

        SL Green OP and ROP have a substantial amount of outstanding indebtedness, a large portion of which is due and payable prior to the maturity of the notes offered hereby. As of March 31, 2011, ROP's and SL Green OP's total consolidated indebtedness was approximately $843.1 million and $5.0 billion (inclusive of ROP's approximately $843.1 million of indebtedness), respectively. In addition, ROP and certain of its subsidiaries also provide a senior guaranty of SL Green OP's obligations under its Credit Facility. ROP and its subsidiaries' respective obligations to guarantee amounts payable under the Credit Facility are limited by the Allocable Guaranty Limitation, as defined in the guaranty agreement under the Credit Facility. As of March 31, 2011, the maximum amount of ROP's guaranty obligation was approximately $359.8 million. SL Green OP's and ROP's respective levels of indebtedness could reduce funds available for additional acquisitions, capital expenditures or other business purposes, impact their respective ratings, restrict their respective financial and operating flexibility or create competitive disadvantages compared to other companies with lower debt levels.

        Our ability to make payments of principal and interest on our indebtedness, including the notes, depends upon our future performance, which will be subject to general economic conditions and financial, business and other factors affecting our consolidated operations, many of which are beyond our control. If we are unable to generate sufficient cash flow from operations in the future to service our respective debt and meet our other cash requirements, we may be required, among other things:

•

to seek additional financing in the debt or equity markets;



•

to refinance or restructure all or a portion of our respective indebtedness, including the notes;



•

to sell selected assets or businesses; or



•

to reduce or delay planned capital or operating expenditures.

        Such measures might not be sufficient to enable us to service our debt and meet our other cash requirements, including the notes. In addition, any such financing, refinancing or sale of assets might not be available at all or on economically favorable terms.

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Since the notes are unsecured, your right to receive payments on the notes is effectively subordinated to all of our existing and future secured debt, and since the notes are not guaranteed by all of our subsidiaries, structurally subordinated to all existing and future liabilities of our subsidiaries that are not co-obligors of the notes.

        The notes are unsecured, senior obligations that rank equal in right of payment with all of SL Green's, SL Green OP's and ROP's existing and future unsecured and senior debt. However, the notes are effectively junior to all of SL Green's, SL Green OP's and ROP's secured debt to the extent of the value of the assets securing that debt. The Indenture governing the notes does not place any limitation on the amount of secured or unsecured senior indebtedness that SL Green or SL Green OP may incur. In any liquidation, dissolution, bankruptcy or other similar proceeding, holders of SL Green's, SL Green OP's or ROP's secured debt may assert rights against any assets securing such debt in order to receive full payment of their debt before those assets may be used to pay the holders of the notes. In such an event, SL Green, SL Green OP or ROP may not have sufficient assets remaining to pay amounts due on any or all of the notes. In addition, the notes are structurally subordinated to all current and future obligations, including subordinated indebtedness and trade payables of SL Green's subsidiaries, other than SL Green OP and ROP. The notes are also structurally subordinated to guarantees of SL Green OP's debt by SL Green OP's subsidiaries other than ROP.

There is no established trading market for the notes, which could limit their market price or the ability to sell them for an amount equal to or higher than their initial offering price.

        The notes are a new issue of securities for which there currently is no trading market. As a result, we cannot provide any assurances that a market will develop for the notes or that you will be able to sell your notes. We do not intend to apply for the notes to be listed on any securities exchange. The underwriters have advised us that they intend to make a market in the notes but they are not obligated to do so and may, in their sole discretion, discontinue any market making in the notes at any time. If any of the notes are traded after their initial issuance, they may trade at a discount from their initial offering price. Future trading prices of the notes will depend on many factors, including prevailing interest rates, the market for similar securities, general economic conditions and our financial condition, performance and prospects.

The limited covenants in the Indenture governing the notes and the terms of the notes will not provide protection against significant events that could adversely impact your investment in the notes.

        The Indenture governing the notes does not:

•

require us to maintain any financial ratios or specific levels of net worth, revenues, income, cash flow or liquidity and, accordingly, does not protect holders of the notes in the event that we experience significant adverse changes in our financial condition or results of operations; or



•

limit the ability of SL Green or SL Green OP to incur additional indebtedness; or



•

prohibit us in certain circumstances from entering into a reorganization, restructuring, merger or similar transaction that may adversely affect the holder of the notes.

        When evaluating the terms of the notes, you should be aware that the terms of the Indenture and the notes will not restrict our ability to engage in, or otherwise be a party to, a variety of corporate transactions, circumstances and events that could have an adverse impact on your investment in the notes.

        Furthermore, any of the original co-obligors under the notes may be released from their obligations as described under "Description of the Notes—Merger, Consolidation or Sale."

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The credit ratings of our indebtedness may not reflect all risks of your investment in the notes.

        The credit ratings of our indebtedness are an assessment by rating agencies of our ability to pay our debts when due. Consequently, real or anticipated changes in any of the credit ratings of our indebtedness will generally affect the market value of the notes. These credit ratings may not reflect the potential impact of risks relating to structure or marketing of the notes. Agency ratings are not a recommendation to buy, sell or hold any security and may be revised or withdrawn at any time by the issuing organization. Each agency's rating should be evaluated independently of any other agency's rating.

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USE OF PROCEEDS

        We estimate that the net proceeds from this offering will be approximately $             million after deducting the underwriting discount and our estimated expenses related to the offering. We intend to use the net proceeds from the sale of the notes offered hereby to repay a portion of the amount outstanding under the Credit Facility and for general corporate purposes and/or working capital purposes, which may include investment opportunities, purchases of the indebtedness of SL Green and its subsidiaries, including SL Green OP and ROP, in the open market from time to time, and the repayment of indebtedness at the applicable maturity or put date. The Credit Facility bears interest at a spread ranging from 70 basis points to 110 basis points over the 30-day LIBOR, based on SL Green's leverage ratio. As of June 30, 2011, the spread was 90 basis points. As of June 30, 2011, approximately $500.0 million was outstanding under the Credit Facility, and availability under the facility was further reduced by the issuance of approximately $54.8 million in letters of credit. See "Description of Other Indebtedness."

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RATIOS OF EARNINGS TO FIXED CHARGES

        The following table shows the ratios of earnings to fixed charges for SL Green, SL Green OP and ROP, respectively:

        The ratios of earnings to fixed charges were computed by dividing earnings by fixed charges. For the purpose of calculating the ratios, the earnings have been calculated by adding fixed charges to income or loss from continuing operations before adjustment for non-controlling interests plus distributions from unconsolidated joint ventures, excluding gains or losses from sale of property, loss on equity investment and marketable securities and the cumulative effect of changes in accounting principles. Fixed charges consist of all interest, whether expensed or capitalized, including the amortization of debt issuance costs and rental expense deemed to represent interest expense. With respect to ROP, all years prior to 2008 have been restated to exclude income from discontinued operations. Excluding the costs associated with SL Green's acquisition of all of the outstanding shares of common stock of Reckson Associates Realty Corp., the 2007 and 2006 ratios would have been 1.46x and 0.75x, respectively. For the year ended December 31, 2006, fixed charges of ROP exceeded earnings by $87.3 million.

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CAPITALIZATION OF SL GREEN

        The following table sets forth SL Green's capitalization as of March 31, 2011 on a historical basis and on an as adjusted basis to reflect the sale of $             million aggregate principal amount of the notes offered hereby. The information set forth in the following table should be read in conjunction with the consolidated financial statements and notes thereto in SL Green's Annual Report on Form 10-K for the year ended December 31, 2010 and SL Green's Quarterly Report on Form 10-Q for the quarter ended March 31, 2011, each of which is incorporated herein by reference.

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SELECTED FINANCIAL DATA OF SL GREEN

        The following table sets forth SL Green's selected financial data and should be read in conjunction with SL Green's Financial Statements and notes thereto included in Item 1, "Financial Statements" and Item 2, "Management's Discussion and Analysis of Financial Condition and Results of Operations" in SL Green's Quarterly Report on Form 10-Q for the quarter ended March 31, 2011 and SL Green's Financial Statements and notes thereto included in Item 8, "Financial Statements and Supplementary Data" and Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations" in SL Green's Annual Report on Form 10-K for the fiscal year ended December 31, 2010, each of which is incorporated herein by reference.

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DESCRIPTION OF OTHER INDEBTEDNESS

Senior Credit Facility

        SL Green OP has a $1.5 billion revolving credit facility (the "Credit Facility"). The Credit Facility bears interest at a spread ranging from 70 basis points to 110 basis points over the 30-day LIBOR, based on SL Green's leverage ratio. As of March 31, 2011, the spread was 90 basis points. The facility matures in June 2012. The facility also requires a 12.5 to 20 basis point fee on the unused balance payable annually in arrears. Approximately $500.0 million was outstanding under the Credit Facility at March 31, 2011, and availability under the facility was further reduced at March 31, 2011 by the issuance of approximately $26.0 million in letters of credit.

        SL Green OP is the borrower, and SL Green and certain of its subsidiaries are guarantors under the Credit Facility. Certain of our indebtedness under the Credit Facility is secured by mortgages granted by subsidiaries of SL Green other than ROP. In the future, we may borrow additional amounts under the Credit Facility to be used by the Credit Facility lenders to acquire a portion of our mortgage indebtedness. Any such mortgages would then secure the Credit Facility up to the acquired amount. Further, ROP and certain of its subsidiaries provide a senior guaranty of SL Green OP's obligations under the Credit Facility. ROP and its subsidiaries' respective obligations to guarantee amounts payable under the Credit Facility are limited by the Allocable Guaranty Limitation, as defined in the guaranty agreement under the Credit Facility. As of March 31, 2011, the maximum amount of ROP's guaranty obligation was approximately $359.8 million.

        The terms of the Credit Facility include certain restrictions and covenants which limit, among other things, the payment of dividends, the incurrence of additional indebtedness, the incurrence of liens and the disposition of assets, and which require compliance with financial ratios relating to the minimum amount of tangible net worth, the minimum amount of debt service coverage, the minimum amount of fixed charge coverage, the maximum amount of unsecured indebtedness, the minimum amount of unencumbered property debt service coverage and certain investment limitations. As of March 31, 2011, SL Green OP was in compliance with all covenants under the Credit Facility.

Debt Securities

Reckson Operating Partnership, L.P., SL Green Realty Corp. and SL Green Operating Partnership, L.P.

7.75% Senior Notes due 2020

        We currently have $250 million aggregate principal amount of our 7.75% senior unsecured notes due 2020 outstanding under the indenture, dated as of March 16, 2010, by and among ROP, SL Green and SL Green OP, as co-obligors, and The Bank of New York Mellon, as trustee (the "7.75% Senior Notes").

        The 7.75% Senior Notes mature on March 15, 2020. The 7.75% Senior Notes bear interest at a rate of 7.75% per annum, computed on the basis of a 360-day year composed of twelve 30-day months and payable on March 15 and September 15 of each year.

        The 7.75% Senior Notes are the unsecured unsubordinated obligations of ROP, SL Green and SL Green OP and rank equally with each entity's existing and future unsecured unsubordinated indebtedness, including the notes. We have the option to redeem all or a part of the 7.75% Senior Notes, at any time or from time to time, at a redemption price equal to 100% of the principal amount of the 7.75% Senior Notes redeemed, plus a "make-whole" premium, and accrued and unpaid interest, if any, to the applicable redemption date.

        The indenture governing the 7.75% Senior Notes contains covenants that, among other things, restrict the ability of ROP and its subsidiaries' to incur additional indebtedness and encumber assets. These covenants are subject to a number of important limitations and exceptions. SL Green and SL

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Green OP are not subject to such restrictions. As of March 31, 2011, we were in compliance with all such covenants.

Reckson Operating Partnership, L.P.

Senior Non-Exchangeable Notes

        ROP currently has the following senior unsecured notes outstanding under the indenture, dated as of March 26, 1999, as amended (the "Existing ROP Indenture"), by and among, ROP, Reckson Associates Realty Corp. and The Bank of New York Mellon (formerly known as The Bank of New York), as trustee (collectively, the "senior notes"). Each series of the senior notes is ROP's unsubordinated unsecured obligation and ranks equally with ROP's notes and with all of ROP's existing and future unsecured senior indebtedness, including the notes:

•

$98.6 million of our 5.875% senior notes due 2014 (the "5.875% Notes") outstanding. The 5.875% Notes will mature on August 15, 2014. Interest on the 5.875% Notes is payable semi-annually in arrears on February 15 and August 15 of each year.



•

$275.0 million of our 6.00% senior notes due 2016 (the "6.00% Notes"). The 6.00% Notes will mature on March 31, 2016. Interest on the 6.00% Notes is payable semi-annually in arrears on May 15 and November 15 of each year.

        ROP can redeem any of the senior notes at any time, in whole or in part, at a redemption price equal to the sum of (i) the principal amount of such series of senior notes (or portion thereof) being redeemed plus accrued interest thereon and (ii) the applicable Make-Whole Amount (as defined in the Existing ROP Indenture), if any, with respect to such senior notes. The Existing ROP Indenture contains covenant provisions that, among other things, include limitations on ROP's ability to incur additional debt and to encumber assets. As of March 31, 2011, ROP was in compliance with all such covenants.

4.00% Exchangeable Senior Debentures due 2025

        As of March 31, 2011, ROP had $657,000 aggregate principal amount of 4.00% senior unsecured debentures due 2025 outstanding under the Existing Indenture, as amended by the first supplemental indenture, dated January 25, 2007, by and among, ROP, Reckson Associates Realty Corp., SL Green and The Bank of New York, as trustee (the "4.00% Debentures"). The 4.00% Debentures are ROP's senior unsecured obligations and rank equally with all of ROP's other unsecured senior indebtedness, including the notes. The 4.00% Debentures are guaranteed by SL Green.

        The 4.00% Debentures will mature on June 15, 2025. Interest on the 4.00% Debentures is payable semi-annually in arrears on June 15 and December 15 of each year. The 4.00% Debentures are redeemable at any time at a redemption price equal to 100% of the principal amount of the 4.00% Debentures plus accrued and unpaid interest (including additional interest), if any. Holders may require us to repurchase their 4.00% Debentures in whole or in part on June 15, 2015 and June 15, 2020 for cash equal to the principal amount of the 4.00% Debentures being repurchased and any unpaid interest accrued thereon.

        Holders of the 4.00% Debentures have the right to convert their 4.00% Debentures into cash, and in certain circumstances, shares of SL Green common stock, prior to the close of business on the second business day prior to the maturity date at any time on or after June 17, 2024. Also, under certain other circumstances, holders can exchange their 4.00% Debentures for cash and, in certain circumstances, shares of SL Green common stock, or a combination thereof. The exchange rate of the 4.00% Debentures is subject to adjustments. As of March 31, 2011, ROP was in compliance with all covenants under the indenture governing the 4.00% Debentures.

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SL Green Operating Partnership, L.P.

3.00% Exchangeable Senior Notes due 2017

        SL Green OP currently has $345.0 million aggregate principal amount of its 3.00% senior unsecured notes due 2017 outstanding under the indenture, dated as of October 12, 2010, by and among SL Green OP, ROP, SL Green and The Bank of New York Mellon, as trustee, with an unconditional guarantee by ROP (the "3.00% Exchangeable Notes due 2017"). The 3.00% Exchangeable Notes due 2017 are guaranteed by ROP.

        The 3.00% Exchangeable Notes due 2017 will mature on October 15, 2017. Interest on the 3.00% Exchangeable Notes due 2017 and the guarantee is payable in arrears semi-annually on April 15 and October 15 of each year. The 3.00% Exchangeable Notes due 2017 and the guarantee are senior unsecured obligations of SL Green OP and ROP, respectively, and rank pari passu with all of SL Green OP's and ROP's respective senior indebtedness, including the notes. The 3.00% Exchangeable Notes due 2017 are structurally subordinated to all existing debt of SL Green's subsidiaries (other than SL Green OP and ROP), including their respective guaranties under the Credit Facility. The 3.00% Exchangeable Notes due 2017 and the guarantee are effectively junior to all of SL Green OP's and ROP's respective existing and future secured debt.

        The 3.00% Exchangeable Notes due 2017 are redeemable by SL Green OP, in whole or in part, at any time to the extent necessary to preserve the qualification of SL Green as a real estate investment trust for U.S. federal income tax purposes. The holders of the 3.00% Exchangeable Notes due 2017 have the option to require SL Green OP, upon the occurrence of certain designated events, to repurchase all of their 3.00% Exchangeable Notes due 2017, in whole or in part, for cash at a purchase price equal to 100% of the principal amount of the 3.00% Exchangeable Notes due 2017 plus accrued and unpaid interest.

        The 3.00% Exchangeable Notes due 2017 are exchangeable for cash and, if applicable, shares of common stock, par value $0.01 per share, of SL Green. If settled in stock, SL Green will deliver shares of its common stock to satisfy any exchange of the notes. The initial conversion price will be approximately $85.81 per share of common stock which represents approximately a 30% conversion premium over the last reported sale price of SL Green's common stock on October 5, 2010, which was $66.01 per share. As of March 31, 2011, SL Green OP was in compliance with all covenants under the indenture governing the 3.00% Exchangeable Notes due 2017.

3.00% Exchangeable Senior Notes due 2027

        As of March 31, 2011, SL Green OP had $123.9 million aggregate principal amount of its 3.00% senior unsecured notes due 2027 outstanding under the indenture, dated as of March 26, 2007, by and among, SL Green, SL Green OP and The Bank of New York, as trustee (the "3.00% Exchangeable Notes due 2027"). These notes are SL Green OP's unsecured obligations and rank equally with all of SL Green OP's other unsecured senior debt. The 3.00% Exchangeable Notes due 2027 are structurally subordinated to all existing debt of SL Green's subsidiaries (other than SL Green OP and ROP), including their respective guaranties under the Credit Facility. The 3.00% Exchangeable Notes due 2017 are effectively junior to all of SL Green OP's and ROP's existing and future secured debt.

        The 3.00% Exchangeable Notes due 2027 will mature on March 30, 2027. Interest on the 3.00% Exchangeable Notes due 2027 is payable in arrears semi-annually on March 30 and September 30 of each year. SL Green OP can redeem the 3.00% Exchangeable Notes due 2027 in whole or in part at any time, to the extent necessary to preserve the qualification of SL Green as a REIT or at any time on or after April 15, 2012, in each case for cash equal to 100% of the principal amount of the 3.00% Exchangeable Notes due 2027 to be redeemed plus accrued and unpaid interest (including additional interest), if any. Holders may require SL Green OP to repurchase their 3.00% Exchangeable Notes due

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2027 in whole or in part on March 30, 2012, March 30, 2017 and March 30, 2022. In addition, holders may require SL Green OP to repurchase their 3.00% Exchangeable Notes due 2027 upon the occurrence of certain designated events set forth in the indenture governing the 3.00% Exchangeable Notes due 2027.

        Holders of the 3.00% Exchangeable Notes due 2027 may exchange their 3.00% Exchangeable Notes due 2027 into cash, and in certain circumstances, shares of SL Green common stock prior to the close of business on the second business day immediately preceding the maturity date beginning on the 22nd scheduled trading day prior to the maturity date, and also under any of the following circumstances:

•

if the closing sale price per share of SL Green common stock for at least 20 trading days in the period of 30 consecutive trading days ending on the last trading day of the preceding calendar quarter is more than 130% of the exchange price per share in effect on the applicable trading day;



•

during the five consecutive trading-day period following any five consecutive trading-day period in which the trading price of the 3.00% Exchangeable Notes due 2027 was less than 98% of the product of the closing sale price per share of SL Green common stock multiplied by the applicable exchange rate;



•

at any time prior to the close of business on the second business day prior to the redemption date if the 3.00% Exchangeable Notes due 2027 have been called for redemption, unless SL Green OP fails to pay the redemption price;



•

if SL Green distributes to all holders of its common stock (a) any rights, warrants or options entitling them for a period of not more than 45 days after the issuance thereof to subscribe to purchase SL Green common stock at an exercise price per share less than the closing sale price of SL Green common stock on the business day immediately preceding the time of announcement of such issuance or (b) assets, debt securities or certain rights to purchase SL Green OP's or SL Green's securities, which distribution has a per share value exceeding 15% of the average of the closing sale price of SL Green common stock for the five consecutive trading days ending on the date immediately preceding the declaration date of such distribution;



•

if SL Green is a party to a share exchange or tender offer or other similar transaction pursuant to which all of the outstanding shares of SL Green common stock would be exchanged for or constitute solely the right to receive cash, securities or other property;



•

upon the occurrence of designated events set forth in the indenture governing the 3.00% Exchangeable Notes due 2027; or



•

if SL Green common stock is not listed on a U.S. national or regional securities exchange for 30 consecutive trading days.

        In these circumstances, holders can exchange their 3.00% Exchangeable Notes due 2027 for cash and, if applicable, shares of SL Green common stock. The initial exchange rate for each $1,000 principal amount of the 3.00% Exchangeable Notes due 2027 is 5.7703 shares of SL Green common stock, payable in cash and, if applicable, shares of SL Green common stock. The exchange rate is subject to adjustments. As of March 31, 2011, SL Green OP was in compliance with all covenants under the indenture governing the 3.00% Exchangeable Notes due 2027.

Junior Subordinated Deferrable Interest Debentures due 2035

        SL Green OP currently has $100.0 million aggregate principal amount of its junior subordinated deferrable interest debentures due 2035 (the "Junior Subordinated Debentures") outstanding. The Junior Subordinated Debentures mature in July 2035. The Junior Subordinated Debentures bear

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interest at a fixed rate of 5.61% for the period from June 2005 to July 2015 and thereafter, the interest rate will float at three month LIBOR plus 1.25%. The Junior Subordinated Debentures are redeemable, at the option of SL Green OP, in whole or in part, with no prepayment premium any time.

Mortgage Financing

        As of March 31, 2011, our total mortgage debt (excluding our share of joint venture debt of approximately $1.7 billion) consisted of approximately $3.0 billion of fixed rate debt, including hedged variable rate debt, with an effective weighted average interest rate of approximately 5.97% and $432.7 million of variable rate debt with an effective weighted average interest rate of approximately 2.04%.

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DESCRIPTION OF THE NOTES

        The notes will be issued under an indenture (the "base indenture"), to be entered into upon the closing of this offering, between us and The Bank of New York Mellon, as trustee (the "Trustee"), as supplemented by a supplemental indenture (the "supplemental indenture," and together with the base indenture, the "Indenture") to be entered into by us and the Trustee. The following is a summary of the material provisions of the Indenture. It does not include all of the provisions of the Indenture. We urge you to read the Indenture because it defines your rights. The terms of the notes include those stated in the Indenture and those made part of the Indenture by reference to the Trust Indenture Act of 1939, or the Trust Indenture Act. The form of base indenture has been filed as Exhibit 4.23 to the registration statement (No. 333-163914) of which this prospectus supplement and the accompanying prospectus form a part, and the supplemental indenture will be filed as an exhibit to a Current Report on Form 8-K to be filed by SL Green, SL Green OP and ROP with the SEC within four business days of the closing of this offering, which will be automatically incorporated by reference into such registration statement. You can find definitions of certain capitalized terms relating to the notes as used in the Indenture in this section.

        The following description of the terms of the notes offered by this prospectus supplement supplements the description of the general terms and provisions of the notes set forth in the accompanying prospectus. You should carefully read this prospectus supplement and the accompanying prospectus to understand fully the terms of the notes. All of the information set forth below is qualified in its entirety by the explanation set forth in the accompanying prospectus, which describes certain general terms and provisions of the debt securities that may be issued under the Indenture from time to time. In the event of any inconsistency between the terms of the notes contained in this prospectus supplement and in the section entitled "Description of Debt Securities" beginning on page 22 of the accompanying prospectus, the terms contained in this prospectus supplement will control with respect to the notes.

        As used in this section, references to the Operating Partnership and ROP, refer only to Reckson Operating Partnership, L.P. and references to "we," "us," and the "co-obligors" refer to SL Green, SL Green OP and ROP. Capitalized terms not otherwise defined herein shall have the meanings given to them in the notes or the Indenture, as applicable.

General

        The notes will be direct, unsecured senior obligations and will rank equally with each other and with all of our other existing and future unsecured senior indebtedness. However, the notes will be effectively junior to our mortgages and other secured indebtedness (to the extent of the collateral securing the same) and structurally subordinated to all liabilities, whether secured or unsecured, and preferred interests of our subsidiaries. As of March 31, 2011, SL Green and its consolidated subsidiaries, including SL Green OP and ROP, had outstanding approximately $1.5 billion of unsecured senior indebtedness (including certain indebtedness under the Credit Facility secured by mortgages granted by subsidiaries of SL Green other than ROP) and approximately $3.4 billion of secured indebtedness (including SL Green OP's share of consolidated joint venture secured indebtedness of approximately $111.7 million and excluding any indebtedness under the Credit Facility secured by mortgages as described above). As of March 31, 2011, SL Green's unconsolidated joint ventures had no unsecured indebtedness outstanding and approximately $3.9 billion of secured indebtedness (including SL Green OP's share of approximately $1.7 billion).

        As of March 31, 2011, the Operating Partnership and its consolidated subsidiaries had outstanding approximately $624.0 million of unsecured senior indebtedness (including any indebtedness under the Credit Facility secured by mortgages as described above) and approximately $219.1 million of consolidated joint venture secured indebtedness (including the Operating Partnership's share of

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consolidated joint venture secured indebtedness of approximately $111.7 million). As of March 31, 2011, the Operating Partnership's unconsolidated joint ventures had no unsecured indebtedness outstanding and approximately $315.0 million of secured indebtedness (including the Operating Partnership's share of unconsolidated joint venture secured indebtedness of approximately $94.5 million). In addition, the Operating Partnership and certain of its subsidiaries provide a senior guaranty of SL Green OP's obligations under its Credit Facility. The Operating Partnership and its subsidiaries' respective obligations to guarantee amounts payable under the Credit Facility are limited by the Allocable Guaranty Limitation, as defined in the guaranty agreement under the Credit Facility. The Operating Partnership's guaranty ranks pari passu in right of payment with the Operating Partnership's other unsecured senior indebtedness. As of March 31, 2011, the maximum amount of the Operating Partnership's guaranty obligation was approximately $359.8 million. The Operating Partnership and its subsidiaries may incur additional indebtedness, including secured indebtedness, subject to the provisions described in this prospectus supplement under "—Certain Covenants—Limitations on Incurrence of Debt." None of SL Green, SL Green OP, their subsidiaries (other than the Operating Partnership and its subsidiaries) nor the Operating Partnership's unconsolidated joint ventures are subject to those limitations.

        The notes will initially be limited to the aggregate principal amount of $             million and will mature on            , 20        , unless we exercise our option to redeem the notes prior to that date.

        We may, without the consent of holders of the notes, increase the principal amount of the notes by issuing additional notes in the future on the same terms and conditions, except for any differences in the issue price and interest accrued prior to the issue date of the additional notes and with the same CUSIP number as the notes offered hereby. The notes offered by this prospectus supplement and any additional notes would rank equally and ratably and would be treated as a single class for all purposes under the Indenture.

        The Indenture does not limit SL Green's or SL Green OP's (or their subsidiaries, other than the Operating Partnership and its subsidiaries) ability to incur additional indebtedness, including secured indebtedness. In addition, the Operating Partnership and its subsidiaries may incur additional indebtedness, including secured indebtedness, subject to the provisions described in this prospectus supplement applicable to the Operating Partnership and its subsidiaries under "—Certain Covenants—Limitations on Incurrence of Debt." ROP's unconsolidated joint ventures are not subject to those limitations.

Payment of Interest

        Interest on the notes will accrue at the rate of        % per year from            , 2011, or the most recent interest payment date to which interest has been paid or provided for, and will be payable in U.S. dollars semi-annually in arrears on        and        of each year, beginning on             , 2012. The interest so payable will be paid to the holder in whose name the note is registered at the close of business on the        or        (whether or not a business day in The City of New York) immediately preceding the applicable interest payment date. Interest on the notes will be computed on the basis of a 360-day year consisting of twelve 30-day months.

Maturity

        The notes will mature on            , 20        , and will be paid in U.S. dollars against presentation and surrender thereof at the corporate trust office of the Trustee. However, we may redeem the notes at our option prior to that date. See "—Optional Redemption." The notes will not be entitled to the benefit of, and are not subject to, any sinking fund.

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Optional Redemption

        We may redeem the notes prior to maturity at any time, in whole or in part from time to time, at our option at a redemption price equal to the sum of (i) the principal amount of the notes being redeemed, (ii) unpaid interest accrued thereon to the redemption date and (iii) the Make-Whole Amount (as defined below), if any, with respect to such notes. If the notes are redeemed on or after            (         days prior to the maturity date of the notes), the redemption price for the notes will equal 100% of the principal amount of the notes, plus unpaid accrued interest thereon to the redemption date. We will, however, pay any interest installment due on an interest payment date which occurs on or prior to a redemption date to holders as of the close of business on the record date immediately preceding such interest payment date. If notice has been given as provided in the Indenture and funds for the redemption of any notes (or any portion thereof) called for redemption shall have been made available on the redemption date referred to in such notice, such notes (or any portion thereof) will cease to bear interest on the date fixed for such redemption specified in such notice and the only right of the holders of such notes will be to receive payment of the redemption price.

        Notice of any optional redemption of notes (or any portion thereof) will be given to holders at their addresses, as shown in the Register, not more than 60 nor less than 30 days prior to the date fixed for redemption. The notice of redemption will specify, among other items, the redemption price, the redemption date and, in the case of a partial redemption, the principal amount of the notes held by such holder to be redeemed. If less than all of the notes are to be redeemed by us, the Trustee shall select, in such manner as it shall deem fair and appropriate, the notes to be redeemed.

        As used herein:

        "Make-Whole Amount" means, in connection with any optional redemption, the excess, if any, of (i) the aggregate present value as of the date of such redemption of each dollar of principal being redeemed and the amount of interest (exclusive of interest accrued to the date of redemption) that would have been payable in respect of each such dollar if such redemption had not been made, determined by discounting, on a semi-annual basis, such principal and interest at the Reinvestment Rate (determined on the third business day in The City of New York preceding the date such notice of redemption is given) from the respective dates on which such principal and interest would have been payable if such redemption had not been made, to the date of such redemption over (ii) the aggregate principal amount of the notes being redeemed.

        "Reinvestment Rate" means        % plus the arithmetic mean of the yields under the heading "Week Ending" published in the most recent Statistical Release under the caption "Treasury Constant Maturities" for the maturity (rounded to the nearest month) corresponding to the remaining life to maturity, as of the redemption date, of the principal being redeemed. If no maturity exactly corresponds to such maturity, yields for the two published maturities most closely corresponding to such maturity shall be calculated pursuant to the immediately preceding sentence and the Reinvestment Rate shall be interpolated or extrapolated from such yields on a straight-line basis, rounding each of such relevant periods to the nearest month. For the purpose of calculating the Reinvestment Rate, the most recent Statistical Release published prior to the date of determination of the Make-Whole Amount shall be used.

        "Statistical Release" means the statistical release designated "H.15 (519)" or any successor publication which is published weekly by the Board of Governors of the Federal Reserve System and which establishes yields on actively traded United States government securities adjusted to constant maturities or, if such statistical release is not published at the time of any determination under the Indenture, then such other reasonably comparable index designated by us.

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Denominations, Interest, Registration and Transfer

        The notes shall be issuable in denominations of $2,000 and any integral multiple of $1,000 in excess thereof. The principal of (and premium, if any) and interest on the notes will be payable at the corporate trust office of the Trustee provided that, at our option, payment of interest may be made by check mailed to the address of the person entitled thereto as it appears in the applicable Register or by wire transfer of funds to the person at an account designated by such person.

        Any interest not punctually paid or duly provided for on any Interest Payment Date with respect to a note ("Defaulted Interest") will forthwith cease to be payable to the holder on the applicable Record Date and may either be paid to the person in whose name the note is registered at the close of business on a special record date (the "Special Record Date") for the payment of the Defaulted Interest to be fixed by the Trustee, notice whereof shall be given to the holder of the note not less than 10 days prior to the Special Record Date, or may be paid at any time in any other lawful manner, all as more completely described in the Indenture.

        Subject to certain limitations imposed upon notes issued in book-entry form, the notes will be exchangeable for other notes of the same series for a like aggregate principal amount of different authorized denominations upon surrender of the notes at the corporate trust office of the Trustee referred to above. In addition, subject to certain limitations imposed upon notes issued in book-entry form, the notes may be surrendered for registration of transfer thereof at the corporate trust office of the Trustee referred to above. Every note surrendered for registration of transfer or exchange shall be duly endorsed or accompanied by a written instrument of transfer. No service charge will be made for any registration of transfer or exchange of any notes, but the Trustee or the co-obligors may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith.

        Neither the co-obligors nor the Trustee shall be required to:

•

register, transfer or exchange any note if the note may be among those selected for redemption during a period beginning at the opening of business 15 days before selection of the notes to be redeemed; or



•

register, transfer or exchange any note so selected for redemption in whole or in part, except, in the case of any note to be redeemed in part, the portion thereof not to be redeemed.

Certain Covenants

        Limitations on Incurrence of Debt.    The Operating Partnership will not, and will not permit any Subsidiary (as defined below) to, incur any Indebtedness (as defined below), other than Permitted Debt (as defined below), if, immediately after giving effect to the incurrence of additional Indebtedness, the aggregate principal amount of all outstanding Indebtedness of the Operating Partnership, and of its Subsidiaries determined at the applicable proportionate interest of the Operating Partnership in each Subsidiary, determined in accordance with GAAP (as defined below), is greater than 60% of the sum of:

        (1)   the Total Assets (as defined below) as of the end of the calendar quarter covered in the Operating Partnership's Annual Report on Form 10-K or Quarterly Report on Form 10-Q, as the case may be, most recently filed with the SEC prior to the incurrence of such additional Indebtedness or, if the Operating Partnership is not then subject to the reporting requirements of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), as of its most recent calendar quarter; and

        (2)   any increase in the Total Assets since the end of the quarter, including, without limitation, any increase in Total Assets resulting from the incurrence of additional Indebtedness (the Total Assets adjusted by this increase are referred to as the "Adjusted Total Assets").

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        The Operating Partnership will not, and will not permit any Subsidiary to, incur any Indebtedness, other than Permitted Debt, if, for the period consisting of the four consecutive fiscal quarters most recently ended prior to the date on which additional Indebtedness is to be incurred, the ratio of Consolidated Income Available for Debt Service (as defined below) to the Annual Service Charge (as defined below) shall have been less than 1.5 to 1, on a pro forma basis after giving effect to the incurrence of Indebtedness and to the application of the proceeds therefrom, and calculated on the assumption that:

•

the Indebtedness and any other Indebtedness incurred by the Operating Partnership or its Subsidiaries since the first day of the four-quarter period and the application of the proceeds therefrom, including to refinance other Indebtedness, had occurred at the beginning of the period,



•

the repayment or retirement of any other Indebtedness by the Operating Partnership or its Subsidiaries since the first day of the four-quarter period had been incurred, repaid or retained at the beginning of the period (except that, in making the computation, the amount of Indebtedness under any revolving credit facility shall be computed based upon the average daily balance of such Indebtedness under the credit facility during the period),



•

any income earned as a result of any increase in Adjusted Total Assets since the end of the four-quarter period had been earned, on an annualized basis, for the period, and



•

in the case of an acquisition or disposition by the Operating Partnership or any of its Subsidiaries of any asset or group of assets since the first day of the four-quarter period, including, without limitation, by merger, stock purchase or sale, or asset purchase or sale, the acquisition or disposition or any related repayment of Indebtedness had occurred as of the first day of the period with the appropriate adjustments with respect to the acquisition or disposition being included in the pro forma calculation of Consolidated Income Available for Debt Service to the Annual Service Charge.

        The Operating Partnership will not, and will not permit any Subsidiary to, incur any Indebtedness secured by any Lien (as defined below) of any kind upon any of the property of the Operating Partnership or any of its Subsidiaries (the "Secured Debt") if, immediately after giving effect to the incurrence of the additional Secured Debt, the aggregate principal amount of all outstanding Secured Debt of the Operating Partnership, and of its Subsidiaries determined at the applicable proportionate interest of the Operating Partnership in each Subsidiary, is greater than 40% of the Adjusted Total Assets.

        Maintenance of Total Unencumbered Assets.    The Operating Partnership will maintain Total Unencumbered Assets (as defined below) of not less than 150% of the aggregate principal amount of all outstanding Unsecured Debt.

        Existence.    Except as permitted under "—Merger, Consolidation or Sale," the Operating Partnership is required to do or cause to be done all things necessary to preserve and keep in full force and effect its existence, all material rights (charter and statutory) and material franchises; provided, however, that the Operating Partnership shall not be required to preserve any such right or franchise if it determines that the preservation thereof is no longer desirable in the conduct of its business.

        Maintenance of Properties.    The Operating Partnership is required to cause all of its material properties used or useful in the conduct of its business or the business of any of its Subsidiaries to be maintained and kept in good condition, repair and working order and supplied with all necessary equipment and to cause to be made all necessary repairs, renewals, replacements, betterments and improvements thereof, all as in the judgment of the Operating Partnership may be necessary so that the business carried on in connection therewith may be properly conducted at all times; provided, however,

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that the Operating Partnership or any of its Subsidiaries shall not be prevented from, among other things, selling or otherwise disposing for value any of its properties in the ordinary course of business.

        Insurance.    The Operating Partnership is required to, and is required to cause each of its Subsidiaries to, keep all of its material properties insured against loss or damage with insurers of recognized responsibility, in commercially reasonable amounts and types.

        Payment of Taxes and Other Claims.    The Operating Partnership is required to pay or discharge or cause to be paid or discharged, before the same shall become delinquent, (1) all taxes, assessments and governmental charges levied or imposed upon it or any of its Significant Subsidiaries or upon the income, profits or property of the Operating Partnership or any of its Significant Subsidiaries, and (2) all lawful claims for labor, materials and supplies which, if unpaid, might by law become a lien upon the property of the Operating Partnership or any of its Significant Subsidiaries; provided, however, that the Operating Partnership shall not be required to pay or discharge or cause to be paid or discharged any such tax, assessment, charge or claim whose amount, applicability or validity is being contested in good faith by appropriate proceedings.

        Provision of Financial Information.    Whether or not SL Green or the Operating Partnership is subject to the reporting requirements of Section 13 or 15(d) of the Exchange Act, SL Green and the Operating Partnership must, and solely to the extent that SL Green OP is subject to the requirements of Section 13 or 15(d) of the Exchange Act, SL Green OP will, provide the Trustee and holders within 15 days after filing, or in the event no such filing is required, within 15 days after the end of the time periods specified in those sections with all quarterly and annual financial information that would be required to be contained in a filing with the SEC on Forms 10-Q and 10-K if SL Green, SL Green OP (if applicable) or the Operating Partnership were required to file such forms; provided that, the foregoing delivery requirements shall be deemed satisfied if the foregoing materials are available on the SEC's EDGAR system or on SL Green's, SL Green OP's or the Operating Partnership's web site within the applicable time period.

        In addition, whether or not required by the SEC, SL Green and the Operating Partnership will, and SL Green OP will, solely to the extent that SL Green OP is subject to the requirements of Section 13 or 15(d) of the Exchange Act, file a copy of all of the information and reports referred to above with the SEC for public availability within the time periods specified in the SEC's rules and regulations.

Defined Terms

        As used herein:

        "Annual Service Charge" as of any date means the amount which is expensed in any 12-month period for interest on Indebtedness.

        "Consolidated Income Available for Debt Service" for any period means Consolidated Net Income of the Operating Partnership and its Subsidiaries (1) plus amounts which have been deducted for (a) interest on Indebtedness of the Operating Partnership and its Subsidiaries, (b) provision for taxes of the Operating Partnership and its Subsidiaries based on income, (c) amortization of debt discount, (d) depreciation and amortization, (e) the effect of any noncash charge resulting from a change in accounting principles in determining Consolidated Net Income for the period, (f) amortization of deferred charges, and (g) provisions for or realized losses on properties and (2) less amounts which have been included for gains on properties.

        "GAAP" means generally accepted accounting principles in the United States, consistently applied, as in effect from time to time.

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        "Indebtedness" means any indebtedness, whether or not contingent, in respect of (1) borrowed money evidenced by bonds, notes, debentures or similar instruments, (2) indebtedness secured by any mortgage, pledge, lien, charge, encumbrance or any security interest existing on property, (3) the reimbursement obligations, contingent or otherwise, in connection with any letters of credit actually issued or amounts representing the balance deferred and unpaid of the purchase price of any property except any balance that constitutes an accrued expense or trade payable or (4) any lease of property as lessee which would be reflected on a balance sheet as a capitalized lease in accordance with GAAP, in the case of items of indebtedness under (1) through (3) above to the extent that any items (other than letters of credit) would appear as a liability on a balance sheet in accordance with GAAP, and also includes, to the extent not otherwise included, any obligation to be liable for, or to pay, as obligor, guarantor or otherwise (other than for purposes of collection in the ordinary course of business), indebtedness of another person.

        "Lien" means, with respect to any person, any mortgage, lien, pledge, charge, security interest or other encumbrance, or any interest or title of any vendor, lessor, lender or other secured party to or of the person under any conditional sale or other title retention agreement or Capital Lease, upon or with respect to any property or asset of the person. A "Capital Lease" is a lease to which the lessee is required concurrently to recognize the acquisition of an asset and the incurrence of a liability in accordance with GAAP.

        "Permitted Debt" means Indebtedness of the Operating Partnership or any Subsidiary owing to any Subsidiary or the Operating Partnership; provided that any Indebtedness is made pursuant to an intercompany note and is subordinated in right of payment to the notes; provided further that any disposition, pledge or transfer of any Indebtedness to a person (other than the Operating Partnership or another Subsidiary) shall be deemed to be an incurrence of Indebtedness by the Operating Partnership or a Subsidiary, as the case may be, and not Permitted Debt.

        "Significant Subsidiary" when used with respect to a person, shall mean a "significant subsidiary" of such person as defined in Article 1, Section 1-02 of Regulation S-X under the Securities Act of 1933, as amended, or the Securities Act.

        "Subsidiary" means any entity of which at the time of determination the Operating Partnership or one or more other Subsidiaries owns or controls, directly or indirectly, more than 50% of the shares of Voting Stock.

        "Total Assets" as of any date means the sum of (1) the Undepreciated Real Estate Assets, (2) all other assets of the Operating Partnership, and of its Subsidiaries determined at the applicable proportionate interest of the Operating Partnership in each Subsidiary, determined in accordance with GAAP (but excluding intangibles and accounts receivable) and (3) the cost of any property of the Operating Partnership, or any Subsidiary thereof, in which the Operating Partnership, or Subsidiary, as the case may be, has a firm, non-contingent purchase obligation.

        "Total Unencumbered Assets" means the sum of (1) those Undepreciated Real Estate Assets not subject to a Lien on a consolidated basis, (2) all other assets of the Operating Partnership, and of its Subsidiaries determined at the applicable proportionate interest of the Operating Partnership in each such Subsidiary, which are not subject to a Lien determined in accordance with GAAP (but excluding intangibles and accounts receivable) and (3) the cost of any property of the Operating Partnership, or any Subsidiary thereof, in which the Operating Partnership, or Subsidiary, as the case may be, has a firm, non-contingent purchase obligation and which is not subject to a Lien; provided, however, that, all investments in any person that is not consolidated with the Operating Partnership for financial reporting purposes in accordance with GAAP shall be excluded from Total Unencumbered Assets.

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        "Undepreciated Real Estate Assets" means as of any date the cost (original cost plus capital improvements) of real estate assets of the Operating Partnership and its Subsidiaries on such date, before depreciation and amortization, determined on a consolidated basis in accordance with GAAP.

        "Unsecured Debt" means Indebtedness of the Operating Partnership or any Subsidiary which is not secured by any mortgage, lien, charge, pledge or security interest of any kind upon any of the properties owned by the Operating Partnership or any of its Subsidiaries.

        "Voting Stock" means stock having general voting power under ordinary circumstances to elect at least a majority of the board of directors, managers or trustees, provided that stock that carries only the right to vote conditionally on the happening of an event shall not be considered Voting Stock whether or not such event shall have happened.

        Except with respect to the covenants described above under "—Certain Covenants—Limitation on Incurrence of Debt" and "—Certain Covenants—Maintenance of Total Unencumbered Assets" with respect to the Operating Partnership and its subsidiaries and below under "—Merger, Consolidation or Sale" with respect to co-obligors, the Indenture does not contain any other provisions that would limit the ability of the Operating Partnership to incur indebtedness or that would afford holders of the notes protection in the case of any of the following events:

•

a highly leveraged or similar transaction involving the Operating Partnership, the management of Operating Partnership or any affiliate of any these parties;



•

a change in control; or



•

a reorganization, restructuring, merger or similar transaction involving the co-obligors that may adversely affect the holders of the notes.

        The indenture does not limit SL Green's or SL Green OP's (or their subsidiaries, other than the Operating Partnership and its subsidiaries) ability to incur additional indebtedness, including secured indebtedness. In addition, the Operating Partnership and its subsidiaries may incur additional indebtedness, including secured indebtedness, subject to the provisions described in this prospectus supplement applicable to the Operating Partnership and its subsidiaries under "—Certain Covenants—Limitations on Incurrence of Debt."

        In addition, subject to the covenants referred to above, the co-obligors may, in the future, enter into certain transactions, such as the sale of all or substantially all of its assets or the merger or consolidation of the co-obligors, that would increase the amount of the co-obligors' indebtedness or substantially reduce or eliminate the co-obligors' assets, which may have an adverse effect on the co-obligors' ability to service its indebtedness, including the notes. In addition, restrictions on ownership and transfers of SL Green's common stock and preferred stock which are designed to preserve its status as a REIT may act to prevent or hinder a change in control.

Merger, Consolidation or Sale

        Any co-obligor may consolidate with, or sell, lease or convey all or substantially all of its assets to, or merge with or into, any other entity, provided that the following conditions are met:

•

any co-obligor, as the case may be, shall be the continuing entity, or the successor entity (if other than co-obligors) formed by or resulting from any consolidation or merger or which shall have received the transfer of assets shall be a person organized and existing under the laws of the United States of America, any state thereof or the District of Columbia and shall expressly assume the due and punctual payment of the principal of (and premium, if any) and interest on all the notes and the performance and observance of all of the covenants and obligations contained in the Indenture;

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•

immediately after giving effect to the transaction, no Event of Default under the Indenture, and no event which, after notice or the lapse of time, or both, would become an Event of Default, shall have occurred and be continuing; and



•

an officer's certificate and legal opinion covering these conditions shall be delivered to the Trustee.

        In addition, a co-obligor or a subsidiary of the co-obligors may directly assume the due and punctual payment of the principal of, any premium and interest on all the notes and the performance of every covenant of the Indenture on the part of the co-obligors to be performed or observed. Upon any assumption, such co-obligor or subsidiary shall succeed to, and be substituted for and may exercise every right and power of the Operating Partnership or the other co-obligor under the Indenture with the same effect as if such co-obligor or subsidiary had been the issuer of the notes and the Operating Partnership or the other co-obligor shall be released from all obligations and covenants with respect to the notes. No assumption shall be permitted unless the co-obligors have delivered to the Trustee (1) an officers' certificate and an opinion of counsel, each stating, among other things, that all obligations and covenants of the Operating Partnership or the other co-obligor in the Indenture remain in full force and effect and (2) an opinion of counsel that the beneficial owners of the notes shall have no materially adverse U.S. federal tax consequences as a result of the assumption, and that, if any notes are then listed on the NYSE, that the notes shall not be delisted as a result of the assumption. Accordingly, any of the original co-obligors can become no longer subject to the Indenture and the covenants therein, if applicable, if the party assuming the obligations is able to satisfy the covenants applicable to the obligor whose obligations have been assumed.

Events of Default, Notice and Waiver

        The Indenture provides that the following events are "Events of Default" with respect to the notes:

        (a)   default for 30 days in the payment of any installment of interest;

        (b)   default in the payment of the principal (or premium, if any) at maturity;

        (c)   default in the performance, or breach, of any other covenant or warranty of the co-obligors contained in the Indenture, the default having continued for 60 days after written notice as provided in the Indenture;

        (d)   the co-obligors, any Subsidiary in which the Operating Partnership has invested at least $50,000,000 in capital or any entity in which the Operating Partnership is the general partner shall fail to pay any principal of, premium or interest on or any other amount payable in respect of, any recourse Indebtedness that is outstanding in a principal or notional amount of at least $50,000,000 (or the equivalent thereof in one or more other currencies), either individually or in the aggregate (but excluding Indebtedness outstanding hereunder), of the Operating Partnership and its consolidated Subsidiaries, taken as a whole, when the same becomes due and payable (whether by scheduled maturity, required prepayment, acceleration, demand or otherwise), and the failure shall continue after the applicable grace period, if any, specified in any agreement or instrument relating to such Indebtedness, or any other event shall occur or condition shall exist under any agreement or instrument evidencing, securing or otherwise relating to such Indebtedness and shall continue after the applicable grace period, if any, specified in the agreement or instrument, if the effect of the event or condition is to accelerate, or to permit the acceleration of, the maturity of such Indebtedness or otherwise to cause, or to permit the holder or holders thereof (or a trustee or

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agent on behalf of the holders) to cause such Indebtedness to mature prior to its stated maturity; or

        (e)   certain events of bankruptcy, insolvency or reorganization, or court appointment of a receiver, liquidator or trustee of the co-obligors or any Significant Subsidiary of any co-obligor or any substantial part of their respective property.

        If an Event of Default under the Indenture occurs and is continuing (other than an Event of Default specified in subsection (e) above, which shall result in an automatic acceleration), then in every case the Trustee or the holders of 25% or more in principal amount of the outstanding notes may declare the principal amount (or, if the notes are Original Issue Discount Securities, the portion of the principal amount as may be specified in the terms thereof) of all of the notes, to be due and payable immediately by written notice thereof to the co-obligors (and to the Trustee if given by the holders). However, at any time after the declaration of acceleration with respect to the notes has been made, but before a judgment or decree for payment of the money due has been obtained by the Trustee, the Event of Default giving rise to such declaration of acceleration shall, without further act, be deemed to have been waived, and such declaration and its consequences shall, without further act, be deemed to have been rescinded and annulled, if:

        (a)   the co-obligors shall have deposited with the Trustee all required payments of the principal of (and premium, if any) and interest on the notes, plus certain fees, expenses, disbursements and advances of the Trustee, and

        (b)   all Events of Default, other than the non-payment of accelerated principal of (or specified portion thereof), or premium (if any) or interest on the notes have been cured or waived as provided in the Indenture.

        The Indenture also provides that the holders of a majority in principal amount of the outstanding notes may waive any past default with respect to the notes and its consequences, except a default in the payment of the principal of (or premium, if any) or interest on any Note.

        The Trustee will be required to give notice to the holders of notes within 90 days of a default under the Indenture unless the default has been cured or waived; provided, however, that the Trustee may withhold notice to the holders of any notes of any default with respect to the notes (except a default in the payment of the principal of (or premium, if any) or interest on any Note) if specified responsible officers of the Trustee consider the withholding to be in the best interest of the holders.

        The Indenture provides that no holder of notes may institute any action, suit or proceeding at law or in equity for the execution of any trust under the Indenture or for the appointment of a receiver or for any other remedy thereunder, unless (i) the holder has given to the Trustee written notice of an Event of Default and of the continuance thereof with respect to the notes, as required under the Indenture, (ii) the holders of at least 25% in aggregate principal amount of the notes then outstanding shall have requested the Trustee to institute such action and offered to the Trustee indemnity reasonably satisfactory to it against the costs, expenses and liabilities to be incurred in compliance with such request and (iii) the trustee shall not have instituted such action within 60 days of such request. This provision will not prevent, however, any holder of notes from instituting suit for the enforcement of payment of the principal of (and premium, if any) and interest on the notes at the respective due dates thereof.

        Subject to provisions in the Indenture relating to its duties in case of default, the Trustee is under no obligation to exercise any of its rights or powers under the Indenture at the request, order or direction of any holders of any notes then outstanding under the Indenture, unless the holders shall have offered to the Trustee thereunder security or indemnity satisfactory to it against the costs, expenses and liabilities which might be incurred by it in compliance with such order, request or direction. The holders of a majority in principal amount of the outstanding notes shall have the right to

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direct the time, method and place of conducting any proceeding for any remedy available to the Trustee, or of exercising any trust or power conferred upon the Trustee. However, the Trustee may refuse to follow any direction if the Trustee being advised by counsel determines that the action so directed may not lawfully be taken or would be unduly prejudicial to holders not joining in such direction or would involve the Trustee in personal liability.

        Within 120 days after the close of each fiscal year, the co-obligors must deliver a certificate of an officer certifying to the Trustee whether or not the officer has knowledge of any default under the Indenture and, if so, specifying each default and the nature and status thereof.

Modification of the Indenture

        Modifications and amendments of the Indenture will be permitted to be made only with the consent of the holders of not less than a majority in principal amount of all outstanding notes which are affected by the modification or amendment; provided, however, that no modification or amendment may, without the consent of the holder of each note affected thereby:

•

extend the Stated Maturity of the principal of, or any installment of interest on, any note, or reduce the principal amount thereof or the interest thereon or any premium payable upon redemption thereof, or extend the Stated Maturity of, or change the place of payment where, or the currency in which the principal of and premium, if any, or interest on such note is denominated or payable, or reduce the amount of the principal of an Original Issue Discount Security that would be due and payable upon a declaration of acceleration of the maturity thereof, change the redemption provision or adversely affect the right or repayment at the option of any holder or impair the right to institute suit for the enforcement of any payment on or after the Stated Maturity thereof (or, in the case of redemption, on or after the redemption date); or



•

reduce the above-stated percentage of outstanding notes necessary to modify or amend the Indenture, to waive compliance with certain provisions thereof or certain defaults and consequences thereunder; or



•

modify any of the foregoing provisions or any of the provisions relating to the waiver of certain past defaults or certain covenants, except to increase the required percentage to effect the action or to provide that certain other provisions may not be modified or waived without the consent of the holder of the note.

        In addition, the co-obligors may not modify, without the written consent of the Trustee, the rights, duties or immunities of the Trustee with respect to the notes under the Indenture.

        In addition to the co-obligors' obligations to pay the principal of, and premium (if any) and interest on, the notes, the Indenture contains several other affirmative and negative covenants as described above under "—Certain Covenants." None of the co-obligors or the Trustee may waive compliance with the other covenants unless the holders of not less than a majority in principal amount of outstanding notes consent to the waiver.

        Modifications and amendments of the Indenture will be permitted to be made by the co-obligors and the Trustee without the consent of any holder of the notes for any of the following purposes:

•

to evidence the succession of another person to one or more of the co-obligors under the Indenture;



•

to add to the covenants and agreements of the co-obligors, and to add Events of Default, in each case for the protection or benefit of the holders of the notes, or to surrender any right or power conferred upon the co-obligors in the Indenture;

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•

to add to or change any of the provisions of the Indenture to provide, change or eliminate any restrictions on the payment of principal of or premium, if any, on the notes, provided that this action shall not adversely affect the interests of the holders of the notes in any material respect;



•

to evidence and provide for the acceptance of appointment by a successor Trustee or facilitate the administration of the trusts under the Indenture by more than one Trustee;



•

to secure the notes;



•

to cure any ambiguity or to correct or supplement any provision contained in the Indenture or in any supplemental indenture which may be mistaken, defective or inconsistent with any other provision contained in the Indenture or in any supplemental indenture;



•

to add to or change or eliminate any provision of the Indenture as shall be necessary or desirable in accordance with any amendments to the Trust Indenture Act;



•

to make any change in the notes that does not adversely affect in any material respect the rights of the holders of such notes;



•

to provide for uncertificated securities in addition to certificated securities;



•

to permit or facilitate the issuance of notes in uncertificated form, provided that this action shall not adversely affect the interests of the holders of the notes in any material respect;



•

to supplement any of the provisions of the Indenture to the extent necessary to permit or facilitate defeasance and discharge of the notes, provided that the action shall not adversely affect the interests of the holders of the notes in any material respect; or



•

to effect the assumption by a subsidiary or a co-obligor pursuant to the Indenture.

        In determining whether the holders of the requisite principal amount of outstanding notes have given any request, demand, authorization, direction, notice, consent or waiver under the Indenture or whether a quorum is present at a meeting of holders of notes, the Indenture provides that:

•

the principal amount of an Original Issue Discount Security that shall be deemed to be outstanding shall be the amount of the principal thereof that would be due and payable as of the date of the determination upon declaration of acceleration of the maturity thereof; and



•

notes owned by the co-obligors or any other obligor upon the notes or any affiliate of the co-obligors or of the other obligor shall be disregarded.

        The Indenture contains provisions for convening meetings of the holders of notes. A meeting may be called at any time by the Trustee, and also, upon request, by the co-obligors or the holders of at least 10% in aggregate principal amount of the outstanding notes, in any case upon notice given as provided in the Indenture. Except for any consent that must be given by the holder of each note affected by certain modifications and amendments of the Indenture, any resolution presented at a meeting or adjourned meeting duly reconvened at which a quorum is present may be adopted by the affirmative vote of the holders of a majority in principal amount of the outstanding notes; provided, however, that, except as referred to above, any resolution with respect to any request, demand, authorization, direction, notice, consent, waiver or other action that may be made, given or taken by the holders of a specified percentage, which is less than a majority, in principal amount of the outstanding notes may be adopted at a meeting or adjourned meeting duly reconvened at which a quorum is present by the affirmative vote of the holders of the specified percentage in principal amount of the outstanding notes. Any resolution passed or decision taken at any meeting of holders of notes duly held in accordance with the Indenture will be binding on all holders of notes. At any meeting called in accordance with the Indenture, the presence of persons holding or representing notes

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in an aggregate principal amount sufficient to take action upon the business for the transaction of which such meeting was called shall be necessary to constitute a quorum.

Discharge, Defeasance and Covenant Defeasance

        The co-obligors may discharge certain obligations to holders of any notes that have not already been delivered to the Trustee for cancellation and that either have become due and payable or will become due and payable within one year (or scheduled for redemption within one year) by irrevocably depositing with the Trustee, in trust, funds in an amount sufficient to pay the entire indebtedness on the notes in respect of principal (and premium, if any) and interest to the date of the deposit (if the notes have become due and payable) or to the Stated Maturity or Redemption Date, as the case may be.

        The Indenture provides that the co-obligors may elect either (a) to defease and discharge themselves from any and all obligations with respect to the notes (except for the obligation to pay additional amounts, if any, upon the occurrence of certain events of tax, assessment or governmental charge with respect to payments on the notes and the obligations to register the transfer or exchange of notes, to replace temporary or mutilated, destroyed, lost or stolen notes, to maintain an office or agency in respect of the notes and to hold moneys for payment in trust) ("defeasance") or (b) to release themselves from their obligations with respect to the notes under certain sections of the Indenture (including the restrictions described under "—Certain Covenants") and, if provided pursuant to the Indenture, their obligations with respect to any other covenant, and any omission to comply with the obligations shall not constitute a default or an Event of Default with respect to the notes ("covenant defeasance"), in either case upon the irrevocable deposit by the co-obligors with the Trustee, in trust, of an amount, in the currency or currencies, currency unit or units or composite currency or currencies in which the notes are payable at Stated Maturity, or Government Obligations (as defined below), or both, applicable to the notes which through the scheduled payment of principal and interest in accordance with their terms will provide money in an amount sufficient to pay the principal of (and premium, if any) and interest on the notes on the scheduled due dates therefor.

        A trust will only be permitted to be established if, among other things, the co-obligors have delivered to the Trustee an Opinion of Counsel (as specified in the Indenture) to the effect that the beneficial owners of the notes will not recognize income, gain or loss for U.S. federal income tax purposes as a result of the defeasance or covenant defeasance and will be subject to U.S. federal income tax on the same amounts, in the same manner and at the same times as would have been the case if the defeasance or covenant defeasance had not occurred, and the Opinion of Counsel, in the case of defeasance, must refer to and be based upon a ruling of the Internal Revenue Service, or the IRS, or a change in applicable U.S. federal income tax law.

        "Government Obligations" means securities which are (1) direct obligations of the United States of America, for the payment of which its full faith and credit is pledged or (2) obligations of a Person controlled or supervised by and acting as an agency or instrumentality of the United States of America, the payment of which is unconditionally guaranteed as a full faith and credit obligation by the United States of America, which, in either case, are not callable or redeemable at the option of the issuer thereof, and shall also include a depository receipt issued by a bank or trust company as custodian with respect to any Government Obligation or a specific payment of interest on or principal of any Government Obligation held by the custodian for the account of the holder of a depository receipt, provided that (except as required by law) the custodian is not authorized to make any deduction from the amount payable to the holder of the depository receipt from any amount received by the custodian in respect of the Government Obligation or the specific payment of interest on or principal of the Government Obligation evidenced by the depository receipt.

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Governing Law

        The Indenture and the notes shall be governed by the laws of the State of New York.

Book-Entry System

        The notes will be issued in the form of one or more fully-registered global notes in book-entry form, which will be deposited with, or on behalf of, The Depository Trust Company ("DTC") and registered in the name of DTC's nominee, Cede & Co. Except as set forth below, the global notes may not be transferred except as a whole by DTC to a nominee of DTC or by a nominee of DTC to DTC or another nominee of DTC or by DTC or any such nominee to a successor of DTC or a nominee of such successor.

        So long as DTC or its nominee is the registered owner of a global note, DTC or its nominee, as the case may be, will be considered the sole holder of the notes represented by such global note for all purposes under the Indenture and the beneficial owners of such notes will be entitled only to those rights and benefits afforded to them in accordance with DTC's regular operating procedures. Except as provided below, owners of beneficial interests in a global note:

•

will not be entitled to have notes represented by the global note registered in their names;



•

will not receive or be entitled to receive physical, certificated notes; and



•

will not be considered the owners or holders of the notes under the Indenture for any purpose, including with respect to the giving of any direction, instruction or approval to the Trustee under the Indenture.

        As a result, each investor who owns a beneficial interest in a global note must rely on the procedures of DTC to exercise any rights of a holder of notes under the Indenture (and, if the investor is not a participant or an indirect participant in DTC, on the procedures of the DTC participant through which the investor owns its interest).

        If with respect to the notes (i) DTC is at any time unwilling or unable to continue as depository or if at any time DTC ceases to be a clearing agency registered under the Exchange Act, and a successor depository is not appointed by us within 90 days, (ii) an Event of Default under the Indenture has occurred and is continuing or (iii) the co-obligors, in their sole discretion, determine at any time that such notes shall no longer be represented by a global note, the co-obligors will issue individual notes in certificated form of the same series and like tenor and in the applicable principal amount in exchange for the notes represented by the global note. In any such instance, an owner of a beneficial interest in a global note will be entitled to physical delivery of individual notes in certificated form of the same series and like tenor, equal in principal amount to such beneficial interest and to have such notes in certificated form registered in its name. Notes so issued in certificated form will be issued in denominations of $2,000 and any integral multiple of $1,000 in excess thereof and will be issued in registered form only, without coupons.

        DTC has advised us that it is:

•

a limited purpose trust company organized under the laws of the State of New York;



•

a "banking organization" within the meaning of the New York Banking Law;



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a member of the Federal Reserve System;



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a "clearing corporation" within the meaning of the New York Uniform Commercial Code; and



•

a "clearing agency" registered under Section 17A of the Exchange Act.

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        DTC was created to hold securities for its participants and to facilitate the clearance and settlement of securities transactions between its participants through electronic book-entry changes to the accounts of its participants. DTC's participants include securities brokers and dealers, including the underwriters; banks and trust companies; clearing corporations and other organizations. Indirect access to DTC's system is also available to others such as banks, brokers, dealers and trust companies; these indirect participants clear through or maintain a custodial relationship with a DTC participant, either directly or indirectly. Investors who are not DTC participants may beneficially own securities held by or on behalf of DTC only through DTC participants or indirect participants in DTC.

        Payments of principal, premium (if any) and interest with respect to the notes represented by a global note will be made by the Trustee to DTC's nominee as the registered holder of the global note. Neither the co-obligors nor the Trustee will have any responsibility or liability for the payment of amounts to owners of beneficial interests in a global note, for any aspect of the records relating to or payments made on account of those interests by DTC, or for maintaining, supervising or reviewing any records of DTC relating to those interests.

        Payments by participants and indirect participants in DTC to the owners of beneficial interests in a global note will be governed by standing instructions and customary industry practice and will be the responsibility of those participants or indirect participants and DTC.

        Transfers between participants in DTC will be effected under DTC's procedures and will be settled in same-day funds. If the laws of a jurisdiction require that certain persons take physical delivery of securities in definitive form, the ability to transfer beneficial interests in a global note to such persons may be limited. Because DTC can only act on behalf of participants, who in turn act on behalf of indirect participants and certain banks, the ability of a person holding a beneficial interest in a global note to pledge its interest to a person or entity that does not participate in the DTC system, or otherwise take actions in respect of its interest, may be affected by the lack of a physical security.

        None of the co-obligors or the underwriters or the Trustee will have any responsibility or liability for any aspect of the records relating to or payments made on account of the beneficial interests in a global note, or for maintaining, supervising or reviewing any records relating to such beneficial interests.

        The information in this section concerning DTC and DTC's system has been obtained from sources that we believe to be reliable, but we take no responsibility for its accuracy.

Same-Day Settlement and Payment

        Settlement for the notes will be made in immediately available funds. We will make all payments of principal, premium, if any, and interest in respect of the notes in immediately available funds while the notes are held in book-entry only form.

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UNDERWRITING

        SL Green Realty Corp., SL Green Operating Partnership, L.P. and Reckson Operating Partnership, L.P., as co-obligors, intend to offer the notes through Wells Fargo Securities, LLC, Merrill Lynch, Pierce, Fenner & Smith Incorporated and Morgan Stanley & Co. LLC, as representatives of the underwriters named below. Subject to the terms and conditions in the underwriting agreement dated the date of this prospectus supplement, each underwriter named below has severally agreed to purchase, and we have agreed to sell to that underwriter, the principal amount of notes set forth opposite the underwriter's name:

        The underwriting agreement provides that the obligations of the underwriters to purchase the notes included in this offering are subject to approval of legal matters by counsel and to other conditions. The underwriters are obligated to purchase all of the notes offered by this prospectus supplement, if any of the notes are purchased. The underwriters reserve the right to reject an order for the purchase of the notes in whole or in part.

        We have agreed in the underwriting agreement to indemnify the underwriters against various liabilities that may arise in connection with this offering, including liabilities under the Securities Act. If we cannot indemnify the underwriters, we have agreed to contribute to payments the underwriters may be required to make in respect of those liabilities.

        The underwriters propose to offer the notes directly to the public at the public offering price indicated on the cover page of this prospectus supplement and to certain dealers at that price less a concession not to exceed        % of the principal amount of the notes. The underwriters may allow, and those dealers may reallow, a concession not to exceed        % of the principal amount of the notes on sales to other dealers. After the public offering of the notes, the public offering price and other selling terms may change.

        In connection with the offering, we expect to incur expenses, excluding the underwriting discount, of approximately $500,000.

        The notes are a new issue of securities for which there currently is no market. We do not intend to apply for the notes to be listed on any securities exchange or to arrange for the notes to be quoted on any quotation system. The underwriters have advised us that they intend to make a market in the notes after completion of the offering and as permitted by applicable law. They are not obligated, however, to make a market in the notes and any market-making may be discontinued at any time at their sole discretion. However, we cannot assure you that the prices at which the notes will sell in the market after this offering will not be lower than the initial offering price or that an active trading market for the notes will develop and continue after this offering. Accordingly, no assurance can be given as to the development or liquidity of any market for the notes.

        In connection with the offering of the notes, certain of the underwriters may engage in transactions that stabilize, maintain or otherwise affect the price of the notes. Specifically, the underwriters may overallot in connection with the offering, creating a short position. In addition, the

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underwriters may bid for, and purchase, the notes in the open market to cover short positions or to stabilize the price of the notes. Any of these activities may stabilize or maintain the market price of the notes above independent market levels, but no representation is made hereby of the magnitude of any effect that the transactions described above may have on the market price of the notes. The underwriters will not be required to engage in these activities, and may engage in these activities, and may end any of these activities, at any time without notice.

        The underwriters and their respective affiliates are full service financial institutions engaged in various activities, which may include securities trading, commercial and investment banking, financial advisory, investment management, investment research, principal investment, hedging, financing and brokerage activities.

        Certain of the underwriters and their affiliates have from time to time provided, and may in the future provide, various investment banking, commercial banking, financial advisory and other services for us for which they have received or will receive customary fees and expenses.

        Certain affiliates of the underwriters are lenders and/or agents under our senior revolving credit facility. To the extent that we use a portion of the net proceeds of this offering to repay borrowings outstanding under our revolving credit facility, those affiliates will receive their proportionate share of any amount of the revolving credit facility that is repaid with the net proceeds from this offering.

        In the ordinary course of their various business activities, the underwriters and their respective affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the accounts of their customers, and such investment and securities activities may involve securities and/or instruments of the issuer. The underwriters and their respective affiliates may also make investment recommendations and/or publish or express independent research views in respect of such securities or instruments and may at any time hold, or recommend to clients that they acquire, long and/or short positions in such securities and instruments.

Notice to Prospective Investors in the European Economic Area

        In relation to each Member State of the European Economic Area which has implemented the Prospectus Directive (each, a "Relevant Member State"), each underwriter has represented and agreed that with effect from and including the date on which the Prospectus Directive is implemented in that Relevant Member State it has not made and will not make an offer of notes which are the subject of the offering contemplated by this prospectus supplement and the accompanying prospectus to the public in that Relevant Member State other than:

        (a)   to any legal entity which is a qualified investor as defined in the Prospectus Directive;

        (b)   to fewer than 100 or, if the Relevant Member State has implemented the relevant provision of the 2010 PD Amending Directive, 150, natural or legal persons (other than qualified investors as defined in the Prospectus Directive), as permitted under the Prospectus Directive, subject to obtaining the prior consent of the representatives for any such offer; or

        (c)   in any other circumstances falling within Article 3(2) of the Prospectus Directive,

provided that no such offer of notes shall require the Company or any underwriter to publish a prospectus pursuant to Article 3 of the Prospectus Directive. For the purposes of this provision, the expression an "offer of notes to the public" in relation to any notes in any Relevant Member State means the communication in any form and by any means of sufficient information on the terms of the offer and the notes to be offered so as to enable an investor to decide to purchase or subscribe the notes, as the same may be varied in that Member State by any measure implementing the Prospectus Directive in that Member State.

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        This prospectus supplement and the accompanying prospectus have been prepared on the basis that any offer of notes in any Relevant Member State will be made pursuant to an exemption under the Prospectus Directive from the requirement to publish a prospectus for offers of notes. Accordingly any person making or intending to make an offer in that Relevant Member State of notes which are the subject of the placement contemplated in this prospectus supplement and the accompanying prospectus may only do so in circumstances in which no obligation arises for the Company or any of the underwriters to publish a prospectus pursuant to Article 3 of the Prospectus Directive, in each case, in relation to such offer. Neither the Company nor the underwriters have authorised, nor do they authorise, the making of any offer of notes in circumstances in which an obligation arises for the Company or the underwriters to publish a prospectus for such offer.

        The expression "Prospectus Directive" means Directive 2003/71/EC (and amendments thereto, including the 2010 PD Amending Directive, to the extent implemented in the Relevant Member State), and includes any relevant implementing measure in the Relevant Member State and the expression "2010 PD Amending Directive" means Directive 2010/73/EU.

Notice to Prospective Investors in the United Kingdom

        This prospectus supplement and the accompanying prospectus are only being distributed to, and are only directed at, (1) persons who are outside the United Kingdom or (2) investment professionals falling within Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005 (the "Order") or (3) high net worth entities, and other persons to whom it may lawfully be communicated, falling within Article 49(2)(a) to (d) of the Order (each such person being referred to as a "relevant person"). The notes are only available to, and any invitation, offer or agreement to subscribe, purchase or otherwise acquire the notes will be engaged in only with, relevant persons. Any person who is not a relevant person should not act or rely on this prospectus supplement or the accompanying prospectus or any of their contents.

        Each underwriter has represented and agreed that:

        (a)   it has only communicated or caused to be communicated and will only communicate or cause to be communicated an invitation or inducement to engage in investment activity (within the meaning of Section 21 of the Finance Service and Market Act 2000 ("FSMA") received by it in connection with the issue or sale of the notes in circumstances in which Section 21(1) of the FSMA does not apply to the Company; and

        (b)   it has complied and will comply with all applicable provisions of the FSMA with respect to anything done by it in relation to the notes in, from or otherwise involving the United Kingdom.

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LEGAL MATTERS

        Certain legal matters will be passed upon for us by Skadden, Arps, Slate, Meagher & Flom LLP, New York, New York, and for the underwriters by Fried, Frank, Harris, Shriver & Jacobson LLP, New York, New York. Ballard Spahr LLP, Baltimore, Maryland, will pass upon certain matters of Maryland law for SL Green Realty Corp. with respect to the notes offered hereby. Certain tax matters will be passed upon for us by Greenberg Traurig, LLP, New York, New York.

EXPERTS

        The consolidated financial statements of SL Green Realty Corp. (including schedule appearing therein), the consolidated financial statements of Rock-Green, Inc. and the consolidated financial statements of 1515 Broadway Realty Corp., each appearing in SL Green Realty Corp.'s Annual Report (Form 10-K) for the year ended December 31, 2010, and the effectiveness of SL Green Realty Corp.'s internal control over financial reporting as of December 31, 2010, have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their reports thereon, included therein, and incorporated herein by reference. Such consolidated financial statements are incorporated herein by reference in reliance upon such reports given on the authority of such firm as experts in accounting and auditing.

        The consolidated financial statements of SL Green Operating Partnership, L.P. (including schedule appearing therein), the consolidated financial statements of Rock-Green, Inc. and the consolidated financial statements of 1515 Broadway Realty Corp., each appearing in SL Green Operating Partnership, L.P.'s Annual Report (Form 10-K) for the year ended December 31, 2010, have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their reports thereon, included therein, and incorporated herein by reference. Such consolidated financial statements are incorporated herein by reference in reliance upon such reports given on the authority of such firm as experts in accounting and auditing.

        The consolidated financial statements of Reckson Operating Partnership, L.P. (including schedule appearing therein) appearing in Reckson Operating Partnership, L.P.'s Annual Report (Form 10-K) for the year ended December 31, 2010, have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their report thereon, included therein, and incorporated herein by reference. Such consolidated financial statements are incorporated herein by reference in reliance upon such report given on the authority of such firm as experts in accounting and auditing.

WHERE YOU CAN FIND MORE INFORMATION; INCORPORATION BY REFERENCE

        Each of SL Green, SL Green OP and ROP are subject to the reporting requirements of the Exchange Act, and in accordance therewith, file annual, quarterly and current reports and other information with the SEC. In addition, SL Green files proxy statements with the SEC. Copies of these reports and other information may be inspected without charge at the SEC's Public Reference Room located at 100 F Street, N.E., Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 for further information on the operation of the Public Reference Room. The SEC maintains an Internet website (http://www.sec.gov) that contains reports, proxy statements and information statements, and other information regarding issuers that file electronically with the SEC. Our SEC filings are also available on our Internet website (http://www.slgreen.com). The information contained on or connected to our website is not, and you must not consider the information to be, a part of this prospectus supplement. Our securities are listed on the NYSE and all such material filed by us with the NYSE also can be inspected at the offices of the NYSE, 20 Broad Street, New York, New York 10005.

        We have filed with the SEC a registration statement on Form S-3, of which this prospectus supplement and the accompanying prospectus are a part, under the Securities Act, with respect to the securities registered hereby. This prospectus supplement and the accompanying prospectus do not

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contain all of the information set forth in the registration statement, certain parts of which are omitted in accordance with the rules and regulations of the SEC. For further information concerning our company and the securities registered hereby, reference is made to the registration statement. Statements contained in this prospectus supplement and the accompanying prospectus as to the contents of any contract or other documents are not necessarily complete, and in each instance, reference is made to the copy of such contract or documents filed as exhibits to the registration statement, each such statement being qualified in all respects by such reference.

        The SEC allows us to "incorporate by reference" information into this prospectus supplement, which means that we can disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus supplement, except for any information superseded by information in this prospectus supplement or any document that we file in the future with the SEC. This prospectus supplement incorporates by reference the documents set forth below that we have previously filed with the SEC and all documents that we file with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act (other than any portion of the respective filings that are furnished pursuant to Item 2.02 or Item 7.01 of a Current Report on Form 8-K (including exhibits related thereto) or other applicable SEC rules, rather than filed) after the date of this prospectus supplement from their respective filing dates. These documents contain important information about us, our business and our finances.

SL Green Realty Corp.

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