Exhibit 31.1

SIZMEK INC. AND SUBSIDIARIES

CERTIFICATION PURSUANT TO RULE 13a-14(a)/15d-14(a)

I, Neil H. Nguyen, certify that:

1.

I have reviewed this Amendment No. 1 to the annual report on Form 10-K of Sizmek Inc.;



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;

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Exhibit 31.1