|Exhibit
31                             
|---------------------------------------
|Rule
13a-14(d)/15d-14(d) Certification.



|I, David Nass,
certify that:
|----------------------------



|1.I have
reviewed this report on Form 10-K and all reports on Form 10-D required
to be filed in respect of the period covered by this report
on Form 10-K of the UBS-Barclays Commercial Mortgage Trust 2012-C4(
the
"Exchange Act periodic reports");
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|2. Based
on my knowledge, the Exchange Act periodic reports, taken as a whole,
do not contain any untrue statement of a material fact or omit to
state a material fact necessary to make the statements made, in light
of the circumstances under which such statements were made, not
misleading
with respect to the period covered by this report;
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|3. Based
on my knowledge, all of the distribution, servicing and other
information
required to be provided under Form 10-D for the period covered
by this report is included in the Exchange Act periodic reports;
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|4.Based
on my knowledge and the servicer compliance statements required in
this report under Item 1123 of Regulation AB, and except as disclosed
in the Exchange Act periodic reports, the servicers have fulfilled
their obligations under the servicing agreements in all material
respects; and
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|5. All of
the reports on assessment of compliance with servicing criteria for
asset-backed
securities and their related attestation reports on assessment of
compliance with servicing criteria for asset-backed securities required
to be
included in this report in accordance with Item 1122 of Regulation AB
and
Exchange Act Rules 13a-18 and 15d-18 have been included as an exhibit to
this
report, except as otherwise disclosed in this report. Any material
instances of noncompliance described in such reports have been
disclosed in this
report on Form 10-K.
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|In giving the
certifications above, I have reasonably relied on
information provided to me by the following unaffiliated parties: Wells
Fargo Bank, National Association,
as Master Servicer, Rialto Capital Advisors, LLC, as Special Servicer,
U.S. Bank National
Association, as Trustee, Certificate Administrator and Custodian,
TriMont Real Estate Advisors,
Inc., as Operating Advisor, CoreLogic Commercial Real Estate Services,
Inc., as Servicing
Function Participant, National Tax Search, LLC, as Servicing Function
Participant, Midland
Loan Services, a Division of PNC Bank, National Association, as Primary
Servicer for the 1000
Harbor Boulevard Mortgage Loan, Rialto Capital Advisors, LLC, as
Special Servicer for
the 1000 Harbor Boulevard Mortgage Loan, Deutsche Bank Trust Company
Americas, as
Trustee, Certificate Administrator, and Custodian for the 1000 Harbor
Boulevard Mortgage
Loan, and Park Bridge Lender Services LLC, as Operating Advisor for the
1000 Harbor Boulevard
Mortgage Loan.
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|Dated: March 31,
2014
|---------------------



|/s/ David Nass
|--------------
|Signature     



|President                                                    
|-------------------------------------------------------------
|(senior officer
in charge of securitization of the depositor)