Exhibit 10.3

EXECUTION COPY

GUARANTY

THIS GUARANTY (as the same may be amended, restated, supplemented or otherwise modified from time to time, this “ Guaranty ”) is made as of September 26, 2007 by each of the Subsidiaries of priceline.com Incorporated (the “ Borrower ”) listed on the signature pages hereto (each an “ Initial Guarantor ”) and those additional Subsidiaries of the Borrower which become parties to this Guaranty by executing a supplement hereto (a “ Guaranty Supplement ”) in the form attached hereto as Annex I (such additional Subsidiaries, together with the Initial Guarantors, the “ Guarantors ”), in favor of JPMorgan Chase Bank, National Association, as Administrative Agent (the “ Administrative Agent ”), for the benefit of the Holders of Secured Obligations under the Credit Agreement described below.  Unless otherwise defined herein, capitalized terms used herein and not defined herein shall have the meanings ascribed to such terms in the Credit Agreement.

W I T N E S S E T H :

WHEREAS, the Borrower, the financial institutions party thereto (collectively, the “ Lenders ”), and the Administrative Agent have entered into that certain Credit Agreement of even date herewith (as the same may be amended, restated, supplemented or otherwise modified from time to time, the “ Credit Agreement ”), which Credit Agreement provides, subject to the terms and conditions thereof, for extensions of credit and other financial accommodations to be made by the Lenders to or for the benefit of the Borrower;

WHEREAS, it is a condition precedent to the extensions of credit by the Lenders under the Credit Agreement that each of the Guarantors (constituting all of the Subsidiaries of the Borrower required to execute this Guaranty pursuant to Section 5.09 of the Credit Agreement) execute and deliver this Guaranty, whereby each of the Guarantors, without limitation and with full recourse, shall guarantee the payment when due of all Secured Obligations, including, without limitation, all principal, interest, letter of credit reimbursement obligations and other amounts that shall be at any time payable by the Borrower under the Credit Agreement or the other Loan Documents; and

WHEREAS, in consideration of the direct and indirect financial and other support and benefits that the Borrower has provided, and such direct and indirect financial and other support and benefits as the Borrower may in the future provide, to the Guarantors, and in consideration of the increased ability of each Guarantor that is a Subsidiary of the Borrower to receive funds through contributions to capital, and for each Guarantor to receive funds through intercompany advances or otherwise, from funds provided to the Borrower pursuant to the Credit Agreement and the flexibility provided by the Credit Agreement for each Guarantor to do so which significantly facilitates the business operations of the Borrower and each Guarantor and in order to induce the Lenders and the Administrative Agent to enter into the Credit Agreement, and to make the Loans and the other financial accommodations to the Borrower and to issue the Letters of Credit described in the Credit Agreement, each of the Guarantors is willing to guarantee the Secured Obligations under the Credit Agreement and the other Loan Documents;

NOW, THEREFORE, in consideration of the foregoing premises and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto agree as follows:

SECTION 1.           Representations, Warranties and Covenants .  Each of the Guarantors represents and warrants to each Lender and the Administrative Agent as of the date of this Guaranty, giving effect to

the consummation of the transactions contemplated by the Loan Documents on the Effective Date, and thereafter on each date as required by Section 4.02 of the Credit Agreement that:

(a)           It (i) is a corporation, partnership or limited liability company duly incorporated or organized, as the case may be, validly existing and in good standing under the laws of its jurisdiction of incorporation or organization, (ii) is duly qualified to do business as a foreign entity and is in good standing (to the extent such concept is applicable) under the laws of each jurisdiction where the business conducted by it makes such qualification necessary, and (iii) has all requisite corporate, partnership or limited liability company power and authority, as the case may be, to own, operate and encumber its property and to conduct its business in each jurisdiction in which its business is conducted or proposed to be conducted, except to the extent failure to do so could not reasonably be expected to result in a Material Adverse Effect.

(b)           It has the requisite corporate, limited liability company or partnership, as applicable, power and authority and legal right to execute and deliver this Guaranty and to perform its obligations hereunder.  The execution and delivery by it of this Guaranty and the performance by each of its obligations hereunder have been duly authorized by proper corporate, limited liability company or partnership proceedings, including any required shareholder, member or partner approval, and this Guaranty constitutes a legal, valid and binding obligation of such Guarantor, enforceable against such Guarantor, in accordance with its terms, except as enforceability may be limited by (i) bankruptcy, insolvency, fraudulent conveyances, reorganization or similar laws relating to or affecting the enforcement of creditors’ rights generally, (ii) general equitable principles (whether considered in a proceeding in equity or at law), and (iii) requirements of reasonableness, good faith and fair dealing.

(c)           Neither the execution and delivery by it of this Guaranty, nor the consummation by it of the transactions herein contemplated, nor compliance by it with the terms and provisions hereof, will (i) conflict with the charter or other organizational documents of such Guarantor, (ii) conflict with, result in a breach of or constitute (with or without notice or lapse of time or both) a default under any law, rule, regulation, order, writ, judgment, injunction, decree or award (including, without limitation, any environmental property transfer laws or regulations) applicable to such Guarantor or any provisions of any indenture, instrument or agreement to which such Guarantor or any of such Guarantor’s Subsidiaries is party or is subject or by which it or its property is bound or affected, or require termination of any such indenture, instrument or agreement, (iii) result in the creation or imposition of any Lien whatsoever upon any of the property or assets of such Guarantor, other than Liens permitted or created by the Loan Documents, or (iv) require any approval of such Guarantor’s board of directors, shareholders, members, partners or unitholders except such as have been obtained.  The execution, delivery and performance by such Guarantor of each of the Loan Documents to which such Guarantor is a party do not and will not require any registration with, consent or approval of, or notice to, or other action to, with or by any Governmental Authority, including under any environmental property transfer act or environmental laws or regulations, except filings, consents or notices which have been made.

                In addition to the foregoing, each of the Guarantors covenants that, so long as any Lender has any Commitment or Letter of Credit outstanding under the Credit Agreement or any amount payable under the Credit Agreement or any other Secured Obligations shall remain unpaid, it will, and, if necessary, will cause the Borrower to, fully comply with those covenants and agreements of the Borrower applicable to such Guarantor set forth in the Credit Agreement.

SECTION 2.           The Guaranty .  Each of the Guarantors hereby unconditionally guarantees, jointly and severally with the other Guarantors, the full and punctual payment and performance when due (whether at stated maturity, upon acceleration or otherwise) of the Secured Obligations, including, without limitation, (i) the principal of and interest on each Loan made to the Borrower pursuant to the

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Credit Agreement, (ii) obligations owing under or in connection with Letters of Credit, (iii) all other amounts payable by the Borrower under the Credit Agreement and the other Loan Documents, and including, without limitation, all Swap Obligations and Banking Services Obligations, and (iv) the punctual and faithful performance, keeping, observance, and fulfillment by the Borrower of all of the agreements, conditions, covenants, and obligations of the Borrower contained in the Loan Documents (all of the foregoing being referred to collectively as the “ Guaranteed Obligations ”).  Upon the failure by the Borrower, or any of its Affiliates, as applicable, to pay punctually any such amount or perform such obligation, subject to any applicable grace or notice and cure period, each of the Guarantors agrees that it shall forthwith on demand pay such amount or perform such obligation at the place and in the manner specified in the Credit Agreement or the relevant other Loan Document, as the case may be.  Each of the Guarantors hereby agrees that this Guaranty is an absolute, irrevocable and unconditional guaranty of payment and is not a guaranty of collection.

SECTION 3.           Guaranty Unconditional .  The obligations of each of the Guarantors hereunder shall be unconditional and absolute and, without limiting the generality of the foregoing, shall not be released, discharged or otherwise affected by:

(i)            any extension, renewal, settlement, indulgence, compromise, waiver or release of or with respect to the Guaranteed Obligations or any part thereof or any agreement relating thereto, or with respect to any obligation of any other guarantor of any of the Guaranteed Obligations, whether (in any such case) by operation of law or otherwise, or any failure or omission to enforce any right, power or remedy with respect to the Guaranteed Obligations or any part thereof or any agreement relating thereto, or with respect to any obligation of any other guarantor of any of the Guaranteed Obligations;

(ii)           any modification or amendment of or supplement to the Credit Agreement, any Swap Agreement, any Banking Services Agreement or any other Loan Document, including, without limitation, any such amendment which may increase the amount of, or the interest rates applicable to, any of the Guaranteed Obligations guaranteed hereby;

(iii)          any release, surrender, compromise, settlement, waiver, subordination or modification, with or without consideration, of any collateral securing the Guaranteed Obligations or any part thereof, any other guaranties with respect to the Guaranteed Obligations or any part thereof, or any other obligation of any person or entity with respect to the Guaranteed Obligations or any part thereof, or any nonperfection or invalidity of any direct or indirect security for the Guaranteed Obligations;

(iv)          any change in the corporate, partnership, limited liability company or other existence, structure or ownership of the Borrower or any other guarantor of any of the Guaranteed Obligations, or any insolvency, bankruptcy, reorganization or other similar proceeding affecting the Borrower or any other guarantor of the Guaranteed Obligations, or any of their respective assets or any resulting release or discharge of any obligation of the Borrower or any other guarantor of any of the Guaranteed Obligations;

(v)           the existence of any claim, setoff or other rights which the Guarantors may have at any time against the Borrower, any other guarantor of any of the Guaranteed Obligations, the Administrative Agent, any Holder of Secured Obligations or any other Person, whether in connection herewith or in connection with any unrelated transactions, provided that nothing herein shall prevent the assertion of any such claim by separate suit or compulsory counterclaim;

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(vi)          the enforceability or validity of the Guaranteed Obligations or any part thereof or the genuineness, enforceability or validity of any agreement relating thereto or with respect to any collateral securing the Guaranteed Obligations or any part thereof, or any other invalidity or unenforceability relating to or against the Borrower or any other guarantor of any of the Guaranteed Obligations, for any reason related to the Credit Agreement, any Swap Agreement, any Banking Services Agreement or any other Loan Document, or any provision of applicable law, decree, order or regulation purporting to prohibit the payment by the Borrower or any other guarantor of the Guaranteed Obligations, of any of the Guaranteed Obligations or otherwise affecting any term of any of the Guaranteed Obligations;

(vii)         the failure of the Administrative Agent to take any steps to perfect and maintain any security interest in, or to preserve any rights to, any security or collateral for the Guaranteed Obligations, if any;

(viii)        the election by, or on behalf of, any one or more of the Holders of Secured Obligations, in any proceeding instituted under Chapter 11 of Title 11 of the United States Code (11 U.S.C. 101 et seq.) (or any successor statute, the “ Bankruptcy Code ”), of the application of Section 1111(b)(2) of the Bankruptcy Code;

(ix)           any borrowing or grant of a security interest by the Borrower, as debtor-in-possession, under Section 364 of the Bankruptcy Code;

(x)            the disallowance, under Section 502 of the Bankruptcy Code, of all or any portion of the claims of the Holders of Secured Obligations or the Administrative Agent for repayment of all or any part of the Guaranteed Obligations;

(xi)           the failure of any other guarantor to sign or become party to this Guaranty or any amendment, change, or reaffirmation hereof; or

(xii)          any other act or omission to act or delay of any kind by the Borrower, any other guarantor of the Guaranteed Obligations, the Administrative Agent, any Holder of Secured Obligations or any other Person or any other circumstance whatsoever which might, but for the provisions of this Section 3 , constitute a legal or equitable discharge of any Guarantor’s obligations hereunder.

SECTION 4.           Discharge Only Upon Payment In Full; Reinstatement In Certain Circumstances .  Each of the Guarantors’ obligations hereunder shall remain in full force and effect until all Guaranteed Obligations shall have been paid in full in cash (other than Unliquidated Obligations that have not yet arisen) and the Commitments and all Letters of Credit issued under the Credit Agreement shall have terminated or expired or, in the case of all Letters of Credit, are fully collateralized on terms reasonably acceptable to the Administrative Agent, at which time, subject to all the foregoing conditions, the guarantees made hereunder shall be terminated.  If at any time any payment of the principal of or interest on any Loan, Secured Obligation or any other amount payable by the Borrower or any other party under the Credit Agreement, any Swap Agreement, any Banking Services Agreement or any other Loan Document is rescinded or must be otherwise restored or returned upon the insolvency, bankruptcy or reorganization of the Borrower or otherwise, each of the Guarantors’ obligations hereunder with respect to such payment shall be reinstated as though such payment had been due but not made at such time.  The parties hereto acknowledge and agree that each of the Guaranteed Obligations shall be due and payable in the same currency as such Guaranteed Obligation is denominated, but if currency control or exchange regulations are imposed in the country which issues such currency with the result that such currency (the “ Original Currency ”) no longer exists or the relevant Guarantor is not able to make payment in such

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Original Currency, then all payments to be made by such Guarantor hereunder in such currency shall instead be made when due in Dollars in an amount equal to the Dollar Amount (as of the date of payment) of such payment due, it being the intention of the parties hereto that each Guarantor takes all risks of the imposition of any such currency control or exchange regulations.

SECTION 5.           General Waivers; Additional Waivers .

(a)           General Waivers .  Each of the Guarantors irrevocably waives acceptance hereof, presentment, demand or action on delinquency, protest, the benefit of any statutes of limitations and, to the fullest extent permitted by law, any notice not provided for herein or under the other Loan Documents, as well as any requirement that at any time any action be taken by any Person against the Borrower, any other guarantor of the Guaranteed Obligations, or any other Person.

(b)           Additional Waivers .  Notwithstanding anything herein to the contrary, each of the Guarantors hereby absolutely, unconditionally, knowingly, and expressly waives, to the fullest extent permitted by law:

(i)            any right it may have to revoke this Guaranty as to future indebtedness or notice of acceptance hereof;

(ii)           (1) notice of acceptance hereof; (2) notice of any Loans, Letters of Credit or other financial accommodations made or extended under the Loan Documents or the creation or existence of any Guaranteed Obligations; (3) notice of the amount of the Guaranteed Obligations, subject, however, to each Guarantor’s right to make inquiry of the Administrative Agent and the Holders of Secured Obligations to ascertain the amount of the Guaranteed Obligations at any reasonable time; (4) notice of any adverse change in the financial condition of the Borrower or of any other fact that might increase such Guarantor’s risk hereunder; (5) notice of presentment for payment, demand, protest, and notice thereof as to