CAFC Reverses PTAB Decision that Invalidated Sanofi Injector Pen Patent

“In evaluating whether a reference is analogous, we have consistently held that a patent challenger must compare the reference to the challenged patent.” – CAFC

Federal CircuitThe U.S. Court of Appeals for the Federal Circuit (CAFC) issued a precedential decision Tuesday that reversed a Patent Trial and Appeal Board (PTAB) decision invalidating claims of Sanofi’s U.S. Patent No. RE47,614, which covers a drug delivery device.

Mylan Pharmaceuticals petitioned the PTAB for inter partes review (IPR) of all 18 claims in Sanofi’s drug injector pen patent. The company argued the patent was invalid due to obviousness, and the PTAB agreed and invalidated the patent.

However, Sanofi appealed to the CAFC and argued that Mylan failed to show that the previous patent was analogous to the ‘614 patent. The appeals court agreed with Sanofi because Mylan only argued that two prior patents were analogous and not the challenged patent.

“The Board’s factual findings regarding analogousness are not supported by substantial evidence,” ruled the CAFC.

The Prior Art

All 18 of the challenged claims in the ‘614 patent are related to “spring washers,” which Sanofi argued allows for a very compact drug delivery device. In the patent, the spring washers require “at least two fixing elements.”

In its IPR petition, Mylan homed in on the spring washers and the necessary fixing elements as grounds for invalidation based on prior art. Mylan argued a patent (Burren) that Sanofi referred to as prior art could be connected to two other patents U.S. Patent No. 2,882,901 (Venezia) and U.S. Patent No. 4,144,957 (de Gennes) by a skilled artisan. Mylan failed to convince the PTAB that Burren in connection with the Venezia patent showed obviousness, but the PTAB ruled that all three patents in connection rendered Sanofi’s ‘614 patent unpatentable.

Sanofi unsuccessfully argued before the PTAB that the de Gennes patent is not analogous to their patent because it relates to cars and not drug delivery devices. While Mylan agreed that the de Gennes patent belongs to a different field, it nonetheless successfully convinced the PTAB that a skilled artisan would be able to see its relevance to Sanofi’s patent.

The PTAB’s ultimate decision was that the de Gennes patent “is reasonably pertinent to axially fixing two components relative towards each other, a problem addressed by the inventors of the ’614 patent.”

Burden of Proof

Sanofi’s main gripe with the PTAB ruling was that the Board analyzed de Gennes’s analogousness to the ‘614 patent when Mylan only presented analogousness arguments related to the Burren patent. According to the pharmaceutical company, this incorrectly shifted the burden of proving the ‘614 patent claims are unpatentable from Mylan to Sanofi.

Sanofi said the Board “adopted Mylan’s problem statement derived from Burren and then worked backward to relate that problem to the ’614 patent,” which resulted in a “legally erroneous conclusion that lacks substantial evidence.”

On the other hand, Mylan made the case that this jump was justified because there is no difference between the problem presented in Burren and Sanofi’s patent.

But, the CAFC agreed here with Sanofi, and the appeals court wrote, “Mylan did not carry its burden to argue that de Gennes is analogous to the ’614 patent.”

The court added that the Board failed to connect its factual findings to substantial evidence related to the de Gennes patent. Thus, the CAFC reversed the decision because the PTAB ruling hinged on the ‘614 patent’s analogousness to de Gennes.

“We have routinely held that the petitioner has the burden of proving unpatentability,” wrote the CAFC.

Analogous Art Test

To come to its reversal decision, the CAFC evaluated the case’s adherence to the analogous art test.

Mylan argued that Sanofi’s application of the analogous art test was too rigid and would overturn the PTAB’s decision “simply because the petition allegedly analyzed the ‘problem’ to be solved in terms of the prior art instead of [the ’614 patent].”

Here, the appeals court once again disagreed with Mylan and wrote, “in evaluating whether a reference is analogous, we have consistently held that a patent challenger must compare the reference to the challenged patent.”

The court said this precedent is backed up by the purpose behind the test, “which is to examine whether a reference can be considered as prior art to the challenged patent in the first place.”

According to the CAFC, the main problem in Mylan’s argument is that it ignored the problems presented in the challenged patent in favor of focusing on the problems presented in the prior art reference.

“Even if a reference is analogous to one problem considered in another reference, it does not necessarily follow that the reference would be analogous to the problems of the challenged patent,” wrote the appeals court judges.

Ultimately, the CAFC’s decision to reverse the unpatentability ruling rested on its determination that Mylan failed to make the analogousness argument that connected the ‘614 patent to de Gennes.



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