FORFEITURE AGREEMENT

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Exhibit 10.20

FORFEITURE AGREEMENT

        FORFEITURE AGREEMENT is made and entered into as of September 8, 2009 (this " Agreement "), by and among (i) PROSPECT ACQUISITION CORP., a Delaware corporation (" Prospect "), (ii) DE GUARDIOLA ADVISORS, INC., a Delaware corporation (" DGA "), (iii) DE GUARDIOLA HOLDINGS, INC., a Delaware corporation (" DGH "), (iv) Flat Ridge Investments LLC, LLM Structured Equity Fund L.P., LLM Investors L.P., CMS Platinum Fund, L.P., SJC Capital LLC, Michael P. Castine, Daniel Gressel, Michael Downey, James J. Cahill and John Merchant (collectively, the " Prospect Founders "), and (v) KENNEDY-WILSON, INC., a Delaware corporation (" KW ").

RECITALS

        WHEREAS, Prospect, KW Merger Sub Corp., a Delaware corporation and wholly-owned subsidiary of Prospect (" Merger Sub ") and KW are concurrently entering into that certain Agreement and Plan of Merger (the " Merger Agreement "; capitalized terms used herein and not otherwise defined shall have the meanings assigned to them in the Merger Agreement), pursuant to which, among other things, Merger Sub will be merged with and into KW, with KW to be the surviving corporation; and

        WHEREAS, as an inducement to KW entering into the Merger Agreement, the Prospect Founders have agreed to forfeit an aggregate of 2,575,000 of their shares of Prospect Common Stock.

        NOW, THEREFORE, in consideration of the covenants, promises and representations set forth herein, and for other good and valuable consideration, and intending to be legally bound hereby, the parties agree as follows:

AGREEMENT

        Section 1     Forfeiture and Cancellation of Prospect Common Stock .    

        (a)   Each of the Prospect Founders agrees that, immediately prior to and contingent upon the Closing under the Merger Agreement, he, she or it shall surrender to Prospect for cancellation stock certificates representing a number of shares of Prospect Common Stock set forth next to each Prospect Founder's name on Schedule 1 hereto under the heading "Shares Forfeited to Prospect" (the " Forfeited Shares ").

        (b)   Each of the Prospect Founders (i) represents and warrants that he, she or it owns his, her or its Forfeited Shares free and clear of liens or encumbrances other than the transfer restrictions set forth in such Prospect Founder's Letter Agreement, dated as of November 14, 2007, by and among such Prospect Founder, Prospect and Citigroup Global Markets Inc. or in that certain Escrow Agreement, dated as of November 14, 2007, by and among Prospect, the Prospect Founders and Continental Stock Transfer & Trust Company, and (ii) agrees that he, she or it shall not incur any additional liens or encumbrances on the Forfeited Shares prior to the Closing under the Merger Agreement.

        (c)   Each of the Prospect Founders acknowledges and agrees that KW would not have entered into the Merger Agreement if the Prospect Founders had not entered into this Agreement concurrently therewith.

        Section 2     Stock Issuance to DGH .    

        (a)   Subject to the terms and conditions and in reliance upon the representations, warranties and agreements set forth herein, at the Closing under the Merger Agreement, in consideration of DGA's engagement by Prospect under the letter agreement, dated as of August 10, 2009, between DGA and Prospect (the " Engagement Letter "), Prospect shall issue to DGH 375,000 shares of Prospect Common Stock (the " Advisor Shares ").

        (b)   DGA agrees that Prospect's delivery of the Advisor Shares shall be in full and complete satisfaction of Prospect's obligation to pay the equity portion of the Transaction Fee pursuant to and as defined in the Engagement Letter.

        Section 3     Representations and Warranties .    Each party hereto hereby represents and warrants to each other party, as of the date hereof and as of Closing, as follows:

        (a)     Power and Authority.     Such party has the full power and authority to enter into this Agreement and to perform its obligations under this Agreement in accordance with the provisions of this Agreement. This Agreement has been duly authorized, executed and delivered by such party and constitutes a legal, valid and binding obligation of such party, enforceable in accordance with its terms, except as enforceability may be limited by applicable bankruptcy, moratorium or other similar laws affecting creditors' rights generally and by general equitable principles.

        (b)     No Conflicts.     The execution and delivery of this Agreement by such party does not, and, the performance of, and compliance with, the terms of this Agreement by such party, will not, (i) conflict with or violate any provision of any law, statute, judgment, injunction, decree, ruling or resolution to which such party is subject, (ii) violate its organizational documents, if applicable, or (iii) conflict with or constitute a default (or an event which, with notice or lapse of time, or both, would constitute a default) under, or result in the breach of, any material agreement or other instrument to which it is a party or that is applicable to such party or any of its assets, or any order or decree applicable to such party.

        (c)     Consents.     No permit, authorization, consent or approval of or by, or any notification of or registration, declaration or filing with, any person (governmental or private) is required to be obtained or made by such party in connection with the execution, delivery and performance by it of this Agreement or the consummation by such party of the transactions contemplated hereby.

        Section 4     Additional Representation and Warranties of DGH .    DGH hereby represents and warrants to Prospect, as of the date hereof and as of Closing, as follows:

        (a)     Accredited Investor.     DGH is an "accredited investor" within the meaning of Rule 501(a) under the Securities Act, and understands that Prospect has relied upon its being an accredited investor in deciding to proceed with the transactions contemplated hereby, and in ascertaining the requirements of law applicable to the issuance of the Advisor Shares pursuant to Section 2 of this Agreement. DGH's financial condition is such that DGH is able to bear all economic risks of investment in the Advisor Shares, including a complete loss of DGH's investments therein. DGH acknowledges that Prospect has provided it with adequate access to financial and other information concerning Prospect as requested and that it has had the opportunity to ask questions of and receive answers from Prospect concerning the transactions contemplated under this Agreement and to obtain therefrom any additional information necessary to make an informed decision regarding an investment in Prospect.

        (b)     Investment.     DGH is acquiring the Advisor Shares from Prospect in a private placement for its own account for investment and not with a view to, or for sale in connection with, any distribution thereof, nor with any present intention of distributing or selling the same, and DGH has no present or contemplated agreement, undertaking, arrangement, obligation, indebtedness or commitment providing for the disposition thereof.

        (c)     Unregistered Securities.     DGH acknowledges and agrees that the Advisor Shares must be held indefinitely until such time as they are subsequently registered under the Securities Act or an exemption from such registration is available. DGH has been advised or is aware of the provisions of Rule 144 promulgated under the Securities Act, which currently permits limited resale of shares purchased in a private placement subject to the satisfaction of certain conditions, including, among

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