FACT Facet Biotech (MM)

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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q/A

(Amendment No. 1)

(Mark One)

For the quarterly period ended September 30, 2009

OR

Commission File Number: 0-19756

Facet Biotech Corporation

(Exact name of registrant as specified in its charter)

1500 Seaport Boulevard

Redwood City, CA 94063

(Address of principal executive offices and Zip Code)

(650) 454-1000

(Registrant’s telephone number, including area code)

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports) and, (2) has been subject to such filing requirements for the past 90 days:  Yes   x  No   o

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T during the  preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).  Yes   o  No   o

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act. (Check one):

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).  Yes  o No  x

As of October 27, 2009, there were 25,067,740 shares of the Registrant’s Common Stock outstanding.

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FACET BIOTECH CORPORATION

INDEX

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Explanatory Note

Facet Biotech Corporation (the Company) is filing this Amendment No. 1 to its Quarterly Report on Form 10-Q for the quarterly period ended September 30, 2009 (the Form 10-Q) as an exhibit-only filing in response to comments received from the staff of the Securities and Exchange Commission regarding a request for confidential treatment of certain portions of Exhibit 10.1 originally filed with the Form 10-Q. This Amendment No. 1 to Quarterly Report on Form 10-Q/A (the Amendment) is being filed solely to re-file Exhibit 10.1. In addition, as required by Rule 12b-15 under the Securities Exchange Act of 1934, as amended, new certifications by our principal executive officer and principal financial officer are filed as exhibits to this Amendment.

Except as described above, the Amendment does not reflect events occurring after the filing of the original Form 10-Q and no revisions are being made pursuant to the Amendment to the Company’s financial statements or any other disclosure contained in the Form 10-Q.

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ITEM 6.                               EXHIBITS

†                   Certain information in this exhibit has been omitted and filed separately with the Securities and Exchange Commission pursuant to a confidential treatment request under 17 C.F.R. Sections 200.80(b)(4) and 24b-2.

* Incorporated by reference to the designated exhibit of Facet Biotech Corporation’s quarterly report on Form 10-Q filed with the SEC on November 3, 2009.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

Dated: April 15, 2010

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