Scott Daniels | September 24, 2012
Judge Sue Robinson of Delaware ruled last week that patentees Senju and Kyorin and their licensee Allergan were precluded from suing Apotex a second time for infringement of a single patent. The dispute between the parties began several years ago when the patentees filed a first action against Apotex for infringement of claims 1-3, 6-7 and 9 of U.S. Patent No. 6,333,045 that claimed compositions comprising gatifloxacin and methods of treating eye disorders with those compositions.
Apotex ultimately prevailed in that first litigation, when Judge Robinson ruled that the asserted claims of the ‘045 patent were invalid over certain prior art references and the CAFC later affirmed her judgment of invalidity. During the pendency of that first litigation, the patentees requested and pursued a reexamination of the ‘045 patent. (They did so, Judge Robinson notes with apparent annoyance, “without the court’s knowledge” or informing Apotex). In that reexamination, the PTO rejected the original ‘045 claims as obvious over the prior art, and the patentees amended their claims to distinguish over that art. Ultimately, the PTO issued a reexamination certificate cancelling claims 1-3 and 8-11 and allowing amended claim 6 and added claims 12-16. The surviving claims were narrower in scope than the original claims.
Toward the end of last year the patentees filed the second action, seeking declaratory judgment that the claims emerging from the reexamination were infringed by the Apotex composition. Apotex moved to dismiss, asserting that the patentees were precluded from bringing the second claim because of the invalidity judgment in the first action.
Judge Robinson agreed with Apotex. First, the Judge found that issue was one of “claim preclusion.” She explained that “[c]laim preclusion bars any new legal claim based on the same legal claim or cause of action.” Applying this general principle to patent cases, she stated that “[e]ach patent, not patent claim, gives rise to an independent and distinct legal claim or cause of action.” Citing the CAFC’s 2012 decision in Aspex Eyewear, Judge Robinson continued that issue of claim preclusion was resolved by considering (1) whether the accused products are “essentially the same” and (2) whether the patent claims being asserted are the same or substantially the same.”
On the first question, patentees contended that the new Apotex composition was different from the old, but Judge Robinson dismissed that contention. On the second question, the patentees argued that they could not have asserted the amended claim and the added claims in the first action because they did not exist at that time. The Judge disagreed: “[w]hile literally true, plaintiffs’ argument is flawed because they could have asserted the equivalent of the new and amended claims in the first litigation.” She explained that the “plaintiffs [had been] free to construe the patent more narrowly than they did.” This earlier possibility might come as a surprise to the patentees. Judge Robinson’s conclusion was that the patentees were precluded from bringing a second claim and dismissed their case.
What will interest post-grant practitioners is the patentee’s citation of two earlier District Court decisions where a patentee was allowed to pursue a second action on a patent obtained through a reissue application. Citing the CAFC’s decision in Aspex Eyewear, Judge Robinson distinguished between reexamination and reissue, in that reissue involves surrender of the original patent and issuance of a new patent, whereas reexamination results in a certificate of the old patent. Further, reexamination might involve a narrowing of the claims, but unlike reissue, it cannot involve a broadening of the claims. She then quoted directly from Aspex: “…reexamination of a patent does not entitle a plaintiff to circumvent claim preclusion because ‘claims that emerge from reexamination do not create a new cause of action that did not exist before.’”
As in Aspex, Judge Robinson found that “none of the claims added or amended during reexamination were broader than their predecessors, and the reexam did not result in a new patent,” so that the claim of the second action was the same as the claim of the first, and patentees were precluded from pursuing it. Judge Robinson then repeated her earlier comment that the patentees had been free to construe their original claims more narrowly in the first action but they failed to do so. “They made a strategic decision not to and lost, and the court will not allow relitigation of the matter.”
No criticism of patentees seems possible since they could not have anticipated in 2010-2011 the CAFC’s 2012 Aspex decision, and the distinctions drawn between reissue and reexamination seem formal not substantive. Still, practitioners will need to heed these differences.