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Clarifying the “by another” standard under the pre-AIA Patent Act
Can an existing patent application invalidate subsequently filed patents if the application and the patents identify overlapping inventors? The U.S. Court of Appeals for the Federal Circuit, which hears all patent-related appeals, recently addressed this issue — and the result was bad news for the holder of the challenged patents.
Is it a joint project?
In 2002, Serono partnered with IVAX Corporation to develop oral cladribine to treat multiple sclerosis (MS). Employees of the two companies met and exchanged confidential information. (Merck acquired Serono in 2006.)
The applications for the patents at issue were filed in December 2004. They covered methods of treating MS by administering cladribine orally in accordance with a specified dosing regimen. The named inventors were four Serono employees involved in the development of the treatment.
Nine months earlier, two IVAX employees who participated in the collaboration had filed an international patent application (referred to as Bodor) for an oral dosing regimen of cladribine. It was for a different invention than Merck’s patents, but the application shared a common disclosure regarding dosing regimens. The application, which named the IVAX employees as inventors, was published on October 14, 2004.
Hopewell Pharma Ventures Inc. filed inter partes review (IPR) challenges to Merck’s patents. The Patent and Trademark Appeal Board (PTAB) found that Bodor and a 1998 medical journal article made Merck’s inventions obvious and therefore unpatentable. Merck appealed.
Note: Because the priority date for the patents here was before March 16, 2013, when relevant provisions of the American Invents Act (AIA) took effect, the court applied the pre-AIA Patent Act.
Who are the joint inventors?
Under pre-AIA law, a patent is invalid if “the invention was described in ... a patent granted on an application for patent by another filed in the United States before the invention by the applicant for patent” (emphasis added). Conversely, one’s own work generally isn’t deemed disqualifying prior art — so a patent issued to the same “inventive entity” doesn’t qualify as prior art that could make an invention obvious.
The PTAB found that, because Merck didn’t present credible evidence that all four of its inventors were joint inventors of Bodor, Bodor wasn’t “one’s own work.” On appeal, the question for the Federal Circuit was whether a disclosure in a prior reference invented by fewer than all the named inventors of a patent (that is, Bodor) can be treated as a disclosure “by another” and included in the prior art — or whether it should be treated as “one’s own work” and excluded.
Merck argued that a reference’s disclosure of the invention of a subset of inventors should be disqualified as prior art against the invention of all of the inventors. Hopewell countered that a prior disclosure is only excluded as the work of the patentee if there’s “complete identity of inventive entity” between the inventors of the disclosure and the challenged patent.
The appellate court sided with Hopewell. When a patented invention is the work of joint inventors, it said, an earlier disclosure can be excluded from prior art only if the parts to be excluded reflect the collective work of the same inventive entity identified in the patent.
It’s not necessary that all of the inventors named in the patent be shown in the disclosure — but the disclosure must reveal the joint work of all of them. Any incongruity between the inventors of a disclosure and the inventors of a patent claim renders the disclosure “by another,” regardless of whether inventors are added to or subtracted from the patent.
Prior art finding prevails
Applying this standard, the appellate court found that Bodor was prior art. The PTAB’s ruling was affirmed, and the proper interpretation of “by another” for pre-AIA purposes was well illustrated.
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