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Exhibit 32.1

Certification of Chief Executive Officer
Pursuant to Section 906 of the
Sarbanes-Oxley Act of 2002

        Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 (18 U.S.C. Section 1350), the undersigned officer of PacWest Bancorp (the "Company"), hereby certifies that the Company's Annual Report on Form 10-K for the year ended December 31, 2011 (the "Report") fully complies with the requirements of Section 13(a) or 15(d), as applicable, of the Securities Exchange Act of 1934 and that the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Dated: March 14, 2012	/s/ MATTHEW P. WAGNER
	Name:	Matthew P. Wagner
	Title:	Chief Executive Officer

        The foregoing certification is being furnished solely pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 (18 U.S.C. Section 1350) and is not being filed as part of the Report or as a separate disclosure document.

Certification of Chief Financial Officer
Pursuant to Section 906 of the
Sarbanes-Oxley Act of 2002

        Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 (18 U.S.C. Section 1350), the undersigned officer of PacWest Bancorp (the "Company"), hereby certifies that the Company's Annual Report on Form 10-K for the year ended December 31, 2011 (the "Report") fully complies with the requirements of Section 13(a) or 15(d), as applicable, of the Securities Exchange Act of 1934 and that the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Dated: March 14, 2012	/s/ VICTOR R. SANTORO
	Name:	Victor R. Santoro
	Title:	Executive Vice President and Chief Financial Officer

        The foregoing certification is being furnished solely pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 (18 U.S.C. Section 1350) and is not being filed as part of the Report or as a separate disclosure document.

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Exhibit 32.1

Certification of Chief Executive Officer Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
Certification of Chief Financial Officer Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002