A Decade of Litigation
Dr. Loeb noted that Enzo has spent about a decade battling rival companies over patent rights long before the latest lawsuits. In the most recent of the earlier cases, the US Federal Circuit ruled in favor of Enzo in 2010. It said that two patents previously invalidated by the US District Court, District of Connecticut, and owned by Enzo in a venture with Yale University were valid.
The two patents—Nos. 5,328,824 and 5,449,767—cover a method of using a compound as a diagnostic probe by attaching a nitrogenous base to a chemical moiety through a linkage group. The patents did not claim the linkage group by structure but by function, stating that it did not substantially interfere with hybridization and detection.
Enzo had sued Applera, a predecessor company to Life Technologies, contending that Applera infringed on those two patents, and two others. Applera, and later Life Tech, countered without success that the patents weren’t specific enough in their description of the claimed invention. The District Court had granted summary judgment to Applera for a third patent, No. 5,082,830, after Enzo agreed it could not prove infringement, while holding that a fourth patent, No. 5,476,928, was anticipated from earlier inventions.
The U.S. Supreme Court declined last June to rehear the Federal Circuit decision. That allowed Enzo to proceed with a new patent-infringement suit in the Connecticut district court, with Life Technologies arguing in response that it used a linkage group that “substantially” interferes with hybridization.
The 180 patent uses some of the same language as the patents at issue in the Applera case, by requiring one of two analogs—compounds similar to purine or deazapurine—that do not “substantially interfere” with hybridization.
Enzo’s case against Applera was one of eight cases involving the four patents that have occurred over the past decade. “The practical fact that these parties have been already battling over these technologies for about 10 years, that probably won’t affect the outcome of the new cases, but certainly affects some atmospherics about the war that’s going on,” Dr. Loeb said.
For one thing, he said, parties in years of patent litigation run an increased risk of having their opponent use against them statements made previously in one of the earlier cases. But the Delaware court will have to evaluate the new litigation independent of the older cases.
Additionally, unlike a civil proceeding, where several lawsuits are often consolidated into a single case, the latest Enzo lawsuits will have to remain separate because of a provision in the new Leahy-Smith America Invents Act, the patent-law overhaul enacted in September.
The rule significantly raises the cost for patentees that initiate litigation. That’s no small concern given Enzo’s smaller revenue base compared to the companies it is suing for infringement. “Roche and Life Tech and Gen-Probe haven’t been dissuaded from using this technology, which either means that there aren’t any good alternatives or alternatively that they’re willing to take the risk on these patent cases that they think eventually they’ll work out or they’ll win, or they think the damages won’t be that big,” Dr. Loeb explained.
Whatever their thinking, the companies sued by Enzo can expect a long court fight, since they are battling a plaintiff that has 11 years left on the 180 patent. Hopefully, it will take far less time than that for the Delaware district court to weigh in or, even better, for the companies involved to settle their dispute.