Exhibit 10.3

AMENDMENT NO. 2 TO  INVESTMENT AGREEMENT

This AMENDMENT NO. 2 (this "Amendment") to that certain Investment Agreement, dated as
of May 6, 2009 and amended as of August 11, 2009 (the "Investment Agreement"), by and among Guaranty Bancorp (the
"Company"), Patriot Financial Partners, L.P., Patriot Financial Partners Parallel, L.P., Relational Investors Mid-Cap Fund
I, L.P., Relational Investors Mid-Cap Fund II, L.P., Castle Creek Capital Partners III, L.P., the other investors named on the signature pages hereto and the other
investors that may become party thereto from time to time subsequent to the date hereof (collectively, the "Investors"), is dated as of
February 11, 2010, by and among the Company and the Investors. Capitalized terms used but otherwise defined in this Amendment shall have the respective meanings ascribed to them in the
Investment Agreement.

WHEREAS,
the Company and the Investors entered into the Investment Agreement pursuant to which they were granted registration rights pursuant to Section 10 thereof with respect to
the Convertible Preferred Stock and the Conversion Securities into which the Convertible Preferred Stock could be converted; and

WHEREAS,
the Company and the Investors desire to amend certain provisions of the Investment Agreement in connection with the Company's compliance with its registration obligations under
Section 10 of the Investment Agreement.

NOW
THEREFORE, in consideration of the foregoing and the mutual covenants herein contained, the parties hereto hereby agree as follows:

Section 1.Amendments.

(a)   A
new definition is hereby added to Section 1 of the Investment Agreement as follows:



(b)   The
definition of "Registrable Securities" in Section 1 of the Investment Agreement is hereby amended and restated in its entirety to read as follows:



(c)   Section 10(a)(i)
of the Investment Agreement is hereby amended and restated in its entirety to read as follows:



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(d)   Section 10(c)(xii)
of the Investment Agreement is hereby amended and restated in its entirety to read as follows:



Section 2.Miscellaneous.

(a)   Each
party hereto hereby acknowledges and confirms that all references in the Investment Agreement to "this Agreement" shall be deemed to include the Investment
Agreement as amended by this Amendment.

(b)   Except
as expressly provided herein, the Investment Agreement shall remain in full force and effect in accordance with the terms thereof.

(c)   For
the convenience of the parties hereto, this Amendment may be executed in any number of counterparts, each of which shall be deemed to be an original instrument, and
all such counterparts will together constitute the same agreement. Executed signature pages to this Amendment may be delivered by facsimile and such facsimiles will be deemed as sufficient as if
actual signature pages had been delivered.

(d)   This
Amendment shall be governed by, construed and enforced in accordance with the laws of the State of Colorado, without giving effect to conflicts of law principles or
other principles that would require the application of any other law.

[Remainder of this page intentionally left blank.]

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IN
WITNESS WHEREOF, the parties have caused this Amendment to be duly executed and delivered as of the date first above written.

GUARANTY BANCORPBy:

/s/ PAUL W. TAYLORName:

Paul W. TaylorTitle:

Executive Vice President, Chief Financial and Operating Officer and SecretaryPATRIOT FINANCIAL PARTNERS, L.P.By:

/s/ W. KIRK WYCOFFName:

W. Kirk WycoffTitle:

Managing PartnerPATRIOT FINANCIAL PARTNERS PARALLEL, L.P.By:

/s/ W. KIRK WYCOFFName:

W. Kirk WycoffTitle:

Managing PartnerCASTLE CREEK CAPITAL PARTNERS III, L.P.By:

/s/ JOHN M. EGGEMEYERName:

John M. EggemeyerTitle:

Managing MemberRELATIONAL INVESTORS MID-CAP FUND I, L.P.By:

/s/ DAVID H. BATCHELDERName:

David H. BatchelderTitle:

PrincipalRELATIONAL INVESTORS MID-CAP FUND II, L.P.By:

/s/ DAVID H. BATCHELDERName:

David H. BatchelderTitle:

Principal


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CONTEXT BH EQUITY FUND II, L.P.By:

CCP BH II, L.P., its General PartnerBy:

BH CCPBH GP, LLC, its General PartnerBy:

BH Equity Research, LLC, its Managing MemberBy:

/s/ ROBERT HENDERSHOTTName:

Robert HendershottTitle:

CEONR INVESTMENTS LIMITED
By its corporate director Artemis Corporate Services LimitedBy:

/s/ DAVID LARKINName:

David LarkinTitle:

DirectorRDV CAPITAL MANAGEMENT LPBy:

RDV Corporation, its General PartnerBy:

/s/ JERRY L. TUBERGENName:

Jerry L. TubergenTitle:

PresidentHERITAGE CAPITAL MANAGEMENT LPBy:

Buttonwood Capital, Inc., its General PartnerBy:

/s/ JERRY L. TUBERGENName:

Jerry L. TubergenTitle:

PresidentRDV CORPORATION SUPPLEMENTAL EXECUTIVE RETIREMENT TRUST (FBO Robert H. Schierbeek)By:

/s/ JERRY L. TUBERGENName:

Jerry L. TubergenTitle:

Duly Authorized Agent


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RANDALL DAMSTRA AND JULIE K. DUISTERHOF, AS JOINTS TEENANTS WITH RIGHT OF SURVIVORSHIP/s/ RANDALL DAMSTRA Randall Damstra/s/ JULIE K. DUISTERHOF Julie K. DuisterhofLISA A. RUH TRUSTBy:

/s/ LISA A. RUHName:

Lisa A. RuhTitle:

Trustee/s/ THEODORE JANUS Theodore Janus/s/ BRYAN BRADFORD Bryan Bradford/s/ BILL BLOCK Bill Block/s/ YVES BEHAR Yves Behar/s/ KEITH BELLING Keith Belling


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