SECURITIES
ADMINISTRATOR WITH AN OPINION OF COUNSEL FOR THE BENEFIT OF
THE TRUSTEE,
MASTER
SERVICER AND THE
SECURITIES
ADMINISTRATOR
AND ON WHICH THEY MAY RELY WHICH IS
SATISFACTORY
TO THE SECURITIES
ADMINISTRATOR
THAT THE
PURCHASE
OF THIS
CERTIFICATE
IS
PERMISSIBLE
UNDER
APPLICABLE
LAW,
WILL NOT
CONSTITUTE
OR RESULT IN A
NON-EXEMPT PROHIBITED
TRANSACTION UNDER SECTION 406 OF ERISA OR SECTION 4975 OF THE CODE AND WILL NOT SUBJECT THE MASTER SERVICER, THE
TRUSTEE OR THE SECURITIES ADMINISTRATOR TO ANY OBLIGATION OR LIABILITY IN ADDITION TO THOSE UNDERTAKEN IN THE AGREEMENT.
ANY RESALE,
TRANSFER OR OTHER DISPOSITION OF THIS CERTIFICATE MAY BE MADE ONLY IF THE PROPOSED TRANSFEREE PROVIDES A
TRANSFER
AFFIDAVIT
TO THE MASTER
SERVICER
AND THE
TRUSTEE
THAT (1) SUCH
TRANSFEREE
IS NOT (A) THE UNITED
STATES,
ANY STATE OR
POLITICAL
SUBDIVISION
THEREOF,
ANY POSSESSION OF THE UNITED STATES, OR ANY AGENCY OR
INSTRUMENTALITY OF ANY OF THE FOREGOING (OTHER
THAN AN
INSTRUMENTALITY
WHICH IS A CORPORATION
IF ALL OF ITS ACTIVITIES ARE SUBJECT TO TAX AND EXCEPT FOR FREDDIE MAC, A MAJORITY OF
ITS BOARD OF DIRECTORS IS NOT SELECTED BY SUCH GOVERNMENTAL UNIT), (B) A FOREIGN
GOVERNMENT,
ANY INTERNATIONAL
ORGANIZATION,
OR ANY
AGENCY OR
INSTRUMENTALITY
OF EITHER OF THE FOREGOING,
(C) ANY ORGANIZATION
(OTHER THAN CERTAIN FARMERS'
COOPERATIVES
DESCRIBED IN
SECTION 521 OF THE CODE) WHICH IS EXEMPT FROM THE TAX IMPOSED BY CHAPTER 1 OF THE CODE UNLESS SUCH
ORGANIZATION
IS SUBJECT TO THE TAX
IMPOSED BY SECTION 511 OF THE CODE (INCLUDING THE TAX IMPOSED BY SECTION 511 OF THE CODE ON UNRELATED
BUSINESS
TAXABLE
INCOME),
(D)
RURAL ELECTRIC AND TELEPHONE
COOPERATIVES
DESCRIBED IN SECTION
1381(a)(2)(C)
OF THE CODE, (E) AN ELECTING LARGE
PARTNERSHIP
UNDER
SECTION 775(a) OF THE CODE (ANY SUCH PERSON
DESCRIBED IN THE FOREGOING
CLAUSES (A), (B), (C), (D) OR (E) BEING HEREIN
REFERRED TO AS
A
"DISQUALIFIED
ORGANIZATION"),
OR (F) AN AGENT OF A
DISQUALIFIED
ORGANIZATION,
(2) NO PURPOSE OF SUCH
TRANSFER IS TO IMPEDE THE
ASSESSMENT OR COLLECTION OF TAX AND (3) SUCH TRANSFEREE
SATISFIES CERTAIN ADDITIONAL
CONDITIONS
RELATING TO THE FINANCIAL
CONDITION
OF THE PROPOSED
TRANSFEREE.
NOTWITHSTANDING THE REGISTRATION IN THE CERTIFICATE
REGISTER OR ANY TRANSFER,
SALE OR OTHER DISPOSITION
OF THIS CERTIFICATE TO A DISQUALIFIED
ORGANIZATION OR AN AGENT OF A DISQUALIFIED
ORGANIZATION,
SUCH REGISTRATION
SHALL BE DEEMED TO
BE OF NO LEGAL FORCE OR EFFECT
WHATSOEVER
AND SUCH PERSON SHALL NOT BE DEEMED TO BE A
CERTIFICATEHOLDER
FOR ANY PURPOSE
HEREUNDER,
INCLUDING, BUT NOT LIMITED TO, THE RECEIPT OF DISTRIBUTIONS ON THIS CERTIFICATE.
Certificate No.1
Percentage Interest: 100%
Class R Residual
Date of Pooling and Servicing Agreement and Cut-off Date:
Aggregate Initial Certificate Principal Balance of this
April 1, 2007
Certificate as of the Cut-off Date:
$0.00
First Distribution Date:
Certificate as of the Cut-off Date:
May 25, 2007
$0.00
Master Servicer:
CUSIP: __________
Wells Fargo Bank, National Association
Assumed Final Distribution Date:
July 25, 2037
BEAR STEARNS ALT-A TRUST 2007-3
MORTGAGE PASS-THROUGH CERTIFICATE
SERIES 2007-3
evidencing a fractional
undivided
interest in the distributions
allocable to the