Cerus (CERS) 10-K/A 2003 FY Annual report (amended)

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Exhibit 31.2

CERTIFICATION

I, Gregory W. Schafer, certify that:

1.

I have reviewed this annual report on Form 10-K/A of Cerus Corporation;

2.

Based on my knowledge, this report does 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;

Date: April 29, 2004

/s/  GREGORY W. SCHAFER      Gregory W. Schafer
Chief Financial Officer

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CERTIFICATION