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EX-31.2 - EXHIBIT 31.2 - MUFG Americas Holdings Corpa2200914zex-31_2.htm
EX-31.1 - EXHIBIT 31.1 - MUFG Americas Holdings Corpa2200914zex-31_1.htm
EX-32.2 - EXHIBIT 32.2 - MUFG Americas Holdings Corpa2200914zex-32_2.htm
10-Q - 10-Q - MUFG Americas Holdings Corpa2200914z10-q.htm

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Exhibit 32.1


CERTIFICATION PURSUANT TO
18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with this Quarterly Report of UnionBanCal Corporation (the "Company") on Form 10-Q for the quarter ending September 30, 2010 as filed with the Securities and Exchange Commission on the date hereof (the "Report"), I, Masashi Oka, President and Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that, to my knowledge:

    (1)
    The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

    (2)
    The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Dated: November 10, 2010

    By:   /s/ MASASHI OKA

Masashi Oka
Chief Executive Officer



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CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002