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Narrowed Reexamined Patent Claims Still Obvious: Federal Circuit
Practical Law Legal Update 9-605-7665 (Approx. 4 pages)
Narrowed Reexamined Patent Claims Still Obvious: Federal Circuit
by Practical Law Intellectual Property & Technology
| Published on 24 Mar 2015 • USA (National/Federal) |
In Senju Pharm. Co. v. Lupin Ltd., the US Court of Appeals for the Federal Circuit affirmed the US District Court for the District of Delaware's decision that the asserted patent claims were invalid for obviousness even though the claims had been narrowed in a recent reexamination.
On March 20, 2015, in Senju Pharmaceutical Co. v. Lupin Ltd., the US Court of Appeals for the Federal Circuit affirmed the US District Court for the District of Delaware's decision that the asserted patent claims were infringed but were invalid for obviousness even though the claims had been narrowed during a recent ex parte reexamination (No. 2013-1630, (Fed. Cir. March 20, 2015)). The decision was consistent with prior litigation which had held the original claims of the patent invalid for obviousness.
Background
The case involved reexamined US Patent No. 6,333,045 (the '045 patent), the claims of which relate to an aqueous liquid pharmaceutical eye drop composition. The district court's decision in this case was the culmination of a series of patent infringement suits asserting the '045 patent, though with some variation in parties and issues involved.
The first of these suits (Apotex 1) began in 2007 when Apotex Inc. and Apotex Corp. (collectively Apotex) filed an Abbreviated New Drug Application (ANDA) with the Food and Drug Administration (FDA) and sought to market a generic version of Allergan's drug product Zymar, which is covered by the claims of the '045 patent. Senju Pharmaceutical Co. sued Apotex under the Hatch-Waxman Act asserting the original claims of the '045 patent. In 2010, the District of Delaware found:
- All the asserted claims were infringed.
- Claims 1-3 and 6-9 were invalid for obviousness.
- Apotex failed to show that claims 6 and 7 were invalid for lack of enablement.
- Apotex failed to demonstrate inequitable conduct.
After a motion for a new trial, the district court reopened the case (Apotex 2) to consider additional evidence on claim 7, but again found the claim invalid for obviousness. The Federal Circuit affirmed the decision.
Before final judgment was entered, Senju filed a petition with the US Patent and Trademark Office (USPTO) for an ex parte reexamination of the '045 patent. Senju submitted the prior art asserted in the litigation, the parties' arguments and the district court's opinion to the USPTO with its petition. The USPTO agreed with the district court that the original claims of the '045 patent would have been obvious over the cited prior art. In October 2011, the USPTO issued a reexamination certificate that:
- Cancelled claims 1-3 and 8-11.
- Allowed amended claim 6.
- Added claims 12-16.
After the reexamination, Senju filed another infringement suit (Apotex 3) against Apotex asserting the narrowed reexamined claims. The District of Delaware dismissed the case on the ground of claim preclusion, and the Federal Circuit affirmed (see Legal Update, No New Cause of Action for Reexamined Patent Claims: Federal Circuit).
In 2011, Senju filed a Hatch-Waxman infringement suit against Lupin and Hi-Tech (Lupin) asserting reexamined claims 6 and 12-16 of the '045 patent. The district court ultimately found that the reexamined claims were infringed, but were invalid for obviousness. Senju appealed the district court's invalidity decision.
Outcome
In a 2-1 decision, the Federal Circuit affirmed the district court's obviousness finding. In the majority opinion, the Federal Circuit:
- Stated that the district court properly applied a presumption of validity to the reexamined claims, requiring Lupin to prove invalidity by clear and convincing evidence.
- Gave deference to the district court's determination that Lupin's experts were more credible than Senju's experts on the issues of obviousness and unexpected results.
- Agreed with the district court's conclusion that although Senju's unexpected results arguments were successful during reexamination, they were too weak when challenged in court, and were insufficient to overcome Lupin's strong obviousness case.
Judge Newman issued a dissenting opinion, in which she criticized the majority's obviousness analysis. Judge Newman stated that the district court and the majority failed to give deference to the USPTO's reexamination by not considering:
- The scope of the reexamined claims.
- The unexpected results at the narrower scope.
- That the prior art teaches away from the reexamined claims.