FIRST AMENDMENT TO STOCKHOLDER'S AGREEMENT

Exhibit 10.26a

FIRST AMENDMENT

TO THE

STOCKHOLDERS AGREEMENT

DATED AS OF D ECEMBER 18, 2003

BETWEEN

F ALCONS A CQUISITION C ORP .

T HE PMI G ROUP , I NC .,

B LACKSTONE C APITAL P ARTNERS IV L.P.,

B LACKSTONE C APITAL P ARTNERS IV-A L.P.,

B LACKSTONE F AMILY I NVESTMENT P ARTNERSHIP IV-A L.P.,

C YPRESS M ERCHANT B ANKING P ARTNERS II L.P.,

C YPRESS M ERCHANT B ANKING II C.V.,

C YPRESS S IDE - BY -S IDE LLC,

55 TH S TREET P ARTNERS II L.P.,

C YPRESS FGIC I NVESTORS LLC,

CIVC/FGIC I NVESTMENT C OMPANY LLC

CIVC P ARTNERS F UND III, L.P.

CIVC P ARTNERS F UND IIIA, L.P.

AND THE

M ANAGEMENT I NVESTORS

FIRST AMENDMENT TO THE STOCKHOLDERS AGREEMENT

This FIRST AMENDMENT TO THE STOCKHOLDERS AGREEMENT (this “ Amendment ”) is made as of December 18, 2003, and is between Falcons Acquisition Corp., a Delaware corporation (the “ Company ”), The PMI Group, Inc., a Delaware corporation (together with any Affiliated transferee within the contemplation of Section 2.5 of the Agreement (as defined below), “ PMI ”), Blackstone Capital Partners IV L.P., a Delaware limited partnership (“ BCP IV ”), Blackstone Capital Partners IV-A L.P., a Delaware limited partnership (“ BCP IV-A ”) and Blackstone Family Investment Partnership IV-A L.P., a Delaware limited partnership (“ BFIP IV-A ,” and together with BCP IV, BCP IV-A and any other Affiliated transferee within the contemplation of Section 2.5, “ Blackstone ”), Cypress Merchant Banking Partners II L.P., a Delaware limited partnership (“ Cypress Onshore ”), Cypress Merchant Banking II C.V., a Netherlands limited partnership (“ Cypress Offshore ”), Cypress Side-by-Side LLC, a Delaware limited liability company (“ Cypress Side-by-Side ”), 55th Street Partners II L.P., a Delaware limited partnership (“ Cypress 55th Street ”), Cypress FGIC Investors LLC, a Delaware limited liability company, as a “Cypress Vehicle” (as described below) (“ Cypress/FGIC ,” and together with Cypress Onshore, Cypress Offshore, Cypress Side-by-Side, Cypress 55th Street, any other “Cypress Vehicle,” any “Cypress Coinvestor” (as described below) and any other Affiliated transferee within the contemplation of Section 2.5 of the Agreement, “ Cypress ”), CIVC/FGIC Investment Company LLC, a Delaware limited liability company, as a “CIVC Vehicle” (as described below) ( “ CIVC/FGIC ” ), CIVC Partners Fund III, L.P., a Delaware limited partnership (“ CIVC Fund III ”), CIVC Partners Fund IIIA, L.P., a Delaware limited partnership (“ CIVC Fund IIIA ”, and together with CIVC/FGIC, CIVC Fund III, any other “CIVC Vehicle” and any other Affiliated transferee within the contemplation of Section 2.5 of the Agreement, “ CIVC ”; and together with PMI, Blackstone and Cypress, the “ Investors ”) and the management investors listed on Annex A and any other management investors who subsequently become a party to this Agreement (the “ Management Investors ”) pursuant to the Agreement. Capitalized terms used and not otherwise defined herein have the meanings set forth in the Stockholders Agreement dated as of August 3, 2003, by and among the Company, PMI, Blackstone and Cypress (the “ Agreement ”).

BACKGROUND

1. Cypress/FGIC has agreed to become party to the Agreement as a Cypress Vehicle and each of the Management Investors listed on Exhibit A hereto (amending Annex A to the Agreement) have agreed to become party to the Agreement as a Management Investor.

2. The parties hereto desire to amend the rights and obligations of the Management Investors under the Agreement.

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NOW, THEREFORE, in consideration of the mutual promises and covenants contained herein, the parties, intending legally to be bound, agree as follows:

1. Amendments to Article I .

(a) Section 1.2 of the Agreement is hereby amended by adding the following definitions in their proper alphabetical order, which, in the event of a conflict with the definitions of terms in the Agreement, shall control:

“ Cause ” means, with respect to a Management Investor, “Cause” as defined in an employment agreement between the Company or any of its subsidiaries and such Management Investor which is entered into as of or after the Closing Date (as the same may be amended in accordance with the terms thereof, an “ Employment Agreement ”) or, if not defined therein or if there is no such agreement, “Cause” means (i) such Management Investor’s continued failure substantially to perform his or her duties (other than as a result of total or partial incapacity due to physical or mental illness) for a period of 10 days following written notice by the Company to such Management Investor of such failure, (ii) dishonesty in the performance of such Management Investor’s duties, (iii) such Management Investor’s conviction of, or plea of nolo contendere to, a crime constituting (A) a felony under the laws of the United States or any state thereof or (B) a misdemeanor involving moral turpitude, (iv) such Management Investor’s willful malfeasance or willful misconduct in connection with such Management Investor’s duties hereunder or any act or omission which is injurious to the financial condition or business reputation of the Company or any of its Affiliates or (v) such Management Investor’s breach of the provisions of Section 9.15 (Covenant Not to Compete; Nonsolicitation) or Section 9.16 (Confidentiality) of this Agreement or the breach of any other confidentiality, non-competition, non-solicitation or proprietary information agreement between such Management Investor and the Company or any of its Affiliates from time to time.

“ Fair Market Value ” means, on a given date, (i) if there is a public market for the shares on such date, the arithmetic mean of the high and low prices of the shares as reported on such date on the composite tape of the principal national securities exchange on which such shares are listed or admitted to trading, or, if no composite tape exists for such national securities exchange on such date, then on the principal national securities exchange on which such shares are listed or admitted to trading, or, if the shares are not listed or admitted on a national securities exchange, the arithmetic mean of the per share closing bid price and per share closing asked price on such date as quoted on the Nasdaq National Market System or such market in which such prices are regularly quoted, or, if no sale of shares shall have been reported on such composite tape or such national securities exchange on such date or quoted on an above referenced market, then the immediately preceding date on which sales of the shares have been so reported or quoted shall be used, and (ii) if there is no public market for the shares on such date, the Fair Market Value shall be the value established by the Company Board in good faith.

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“ Family Group Members ” means, with respect to a Management Investor, such Management Investor’s spouse, parent, descendant, stepchild or stepgrandchild or any executor, estate, guardian, committee, trustee or other fiduciary acting as such solely on behalf or solely for the benefit of any such spouse, parent, descendant, stepchild or stepgrandchild.

“ Management Entity ” means, with respect to a Management Investor, (i) such Management Investor, (ii) such Management Investor’s Management Trust, and (iii) the conservators, guardians, executors, administrators, testamentary trustees, legatees or beneficiaries of such Management Investor.

“ Management Trust ” means, with respect to a Management Investor, a limited partnership, limited liability company, trust or custodianship, the beneficiaries of which may include only such Management Investor, his spouse (or ex-spouse) or his lineal descendants (including adopted) or, if at any time after any such transfer there shall be no then living spouse or lineal descendants, then to the ultimate beneficiaries of any such trust or to the estate of a deceased beneficiary.

“ Permanent Disability ” means, with respect to a Management Investor, such Management Investor becomes physically or mentally incapacitated and is therefore unable for a period of at least 180 days in any 12 consecutive month period, to perform the Management Investor’s duties with the Company or any subsidiary or Affiliate thereof. Any question as to the existence of the Permanent Disability of the Management Investor as to which the Management Investor and the Company cannot agree shall be determined in writing by a qualified independent physician mutually acceptable to the Management Investor and the Company. If the Management Investor and the Company cannot agree as to a qualified independent physician, each shall appoint such a physician and those two physicians shall select a third who shall make such determination in writing. The determination of Permanent Disability made in writing to the Company and the Management Investor shall be final and conclusive for all purposes of this Agreement.

(b) Section 1.2 of the Agreement is hereby amended by adding the following information to the table in Section 1.2 in the proper alphabetical order:

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2. Amendments to Article II .

(a) Section 2.2(a) of the Agreement is hereby amended by deleting it in its entirety and replacing it with following Section 2.2(a):

(a) The “ Transfer Restriction Period ” shall begin on the Closing Date and shall end: (i) with respect to any Investor, on the later to occur of (Y) the earlier to occur of the date of consummation of the Qualified IPO and the fifth anniversary of the Closing Date and (Z) the date that the Preferred Shares (and any shares of the Class B Common Stock into which such Preferred Shares may have been converted) are redeemed in full (or otherwise cease to be outstanding) and (ii) with respect to any Management Investor, on the later to occur of (Y) the date of the earliest to occur (the “ Lapse Date ”) of (1) Blackstone and Cypress, collectively, ceasing to Control Equity Securities representing at least 50% of Blackstone’s and Cypress’ aggregate Original Equity Stake, (2) the occurrence of a Company Sale and (3) the fifth anniversary of the Closing Date, and (Z) the date that the Preferred Shares (and any shares of the Class B Common Stock into which such Preferred Shares may have been converted) are redeemed in full (or otherwise cease to be outstanding); provided , however , that the restrictions set forth in clause (ii) shall lapse prior to the Lapse Date in connection with, and following, a Qualified IPO such that the restrictions set forth in clause (ii) shall only continue to apply in connection with, and following, a Qualified IPO to, a number of shares of Equity Securities owned or Controlled by such Management Investor, from time to time, that is equal to the product of (y) the number of shares of Equity Securities owned or Controlled by such Management Investor immediately prior to the Qualified IPO and (z) the percentage of Blackstone’s and Cypress’ aggregate Original Equity Stake then Controlled by Blackstone and Cypress in the aggregate. During the Transfer Restriction Period, none of the Investors, the Management Investors or any of their respective Permitted Transferees shall, directly or indirectly, Transfer any Equity Securities except in accordance with Sections 2.3, 2.5, 2.13, 2.14 or 2.15. Registrable Securities may, subject to the preceding sentence, be Transferred by Investors in the Qualified IPO in accordance with the piggyback registration rights described in Section 6.2.

(b) Section 2.5(a) of the Agreement is hereby amended by deleting the words “any other Investor” in the first sentence of Section 2.5(a) and replacing such words with “any other party hereto”.

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(c) Section 2.7(a) of the Agreement is hereby amended by deleting it in its entirety and replacing it with the following Section 2.7(a):

(a) In the event that the rights of first offer set forth in Section 2.9 are not exercised, any Investor or Permitted Transferee of any Investor proposing to Transfer any Equity Securities (a “ Transferring Investor ”) after the end of the Transfer Restriction Period, or as otherwise permitted under Section 2.2(c), but prior to the Qualified IPO, shall be entitled to Transfer such Equity Securities during the time periods set forth in Section 2.9(e) and (f) subject to the following. The Transferring Investor shall have the obligation, and each other Investor, Management Investor and Permitted Transferee (for purposes of this Section 2.7, the “ Other Investors ”) who is not then in breach of this Agreement shall have the right, to include a number of shares of each class of Equity Securities in such proposed Transfer, at the same price per security and upon the same terms and conditions as to be paid and given to the Transferring Investor(s), equal to the product (rounded up to the nearest whole number) of (i) a fraction, the numerator of which is the number of shares of such class of Equity Securities being Transferred held by such Other Investor and the denominator of which is the number of shares of such class of Equity Securities held by the Transferring Investor and all of the Investors seeking to exercise tag-along rights pursuant to this Section 2.7, multiplied by (ii) the number of shares of such class of Equity Securities proposed to be sold in the contemplated sale. The Other Investors must agree to make substantially the same representations, warranties, covenants and indemnities and other similar agreements as the Transferring Investor(s) agree to make in connection with the proposed Transfer of the Equity Securities of the Transferring Investor(s).

(d) Section 2.9(a) of the Agreement is hereby amended by deleting the first sentence of such section it in its entirety and replacing it with the following first sentence of Section 2.9(a):

Except as set forth in Section 2.9(h), and subject to the last sentence of Section 8.2, each Investor, Management Investor, Management Entity, and Family Group Member seeking to Transfer any shares of Common Stock held by it prior to the Qualified IPO and after its respective Transfer Restriction Period or as otherwise permitted under Section 2.2(c) (a “ Selling Investor ”) must first comply with the provisions of this Section 2.9 and, if applicable, Section 2.7 (Tag-Along Rights).

(e) Section 2.9(f) of the Agreement is hereby amended by replacing the words “selling Investor” with “Selling Investor”.

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(f) Article II of the Agreement is hereby amended by adding, immediately following Section 2.12, the following new Sections 2.13, 2.14 and 2.15:

2.13 Certain Transfers by Management Investors .

(a) Notwithstanding anything in this Agreement to the contrary, each Management Investor is entitled, from time to time, without the consent of any other party hereto, to Transfer any or all of the Common Stock owned by it to a Family Group Member or Management Trust. As a condition to any such Transfer, any such transferee must execute and deliver to the Company an instrument in form and substance reasonably satisfactory to the Company agreeing to be bound hereby as a Permitted Transferee.

(b) Notwithstanding any provision in the Agreement to the contrary, the Company may, from time to time, permit any Management Investor to Transfer any shares held by such Management Investor to the Company without complying with the requirements set forth in this Article II other than the requirements set forth in Section 2.4.

2.14 Call Rights .

(a) If, prior to the Lapse Date, a Management Investor ceases to be employed by the Company or any subsidiary of the Company for any reason (a “ Termination ”), the Company and the Investors will have the rights (the “ Call Rights ”) specified below to purchase the Common Stock held by such Management Investor and his Permitted Transferees.

(b) In the event of a Termination of a Management Investor for any reason other than Cause, the Company will have the right (but not the obligation) to purchase from such Management Investor and his Permitted Transferees, and such Management Investor and his Permitted Transferees will be required to sell to the Company any or all of the Common Stock held by such Management Investor and his Permitted Transferees at a price per share equal to the Fair Market Value as of the date the Company first exercises such Call Right with respect to such Management Investor. In the event of a Termination of such Management Investor for Cause, the Company (or any of its assignees) will have the right (but not the obligation) to purchase from such Persons, and such Persons will be required to sell to the Company (or to any such assignee) any or all of his Common Stock (including any fractional shares) at a price per share equal to the lower of (i) the price per share paid for such Common Stock by such Management Investor, provided that if the price per share paid for such Common Stock is zero, then the price per share paid will be deemed to be the par value and (ii) the Fair Market Value as of the date the Company first exercises such Call Right with respect to such Management Investor. With respect to any particular shares of Common Stock, the Company will have such Call Rights for a period commencing on the date (the “ Call Commencement Date ”) that is the later of (A) the date of the Termination, and (B) in the case of Common Stock received upon the exercise of Common Stock Equivalents, the date of the exercise of such Common Stock Equivalents.

(c) The Company will be entitle