Multiple Factors Drive Downtrend in Amendments at PTAB
Post-issuance amendment of patents has never been popular among patentees. This is because such amendments typically trigger an intervening rights defense that bars the collection of past damages from accused infringers. That is, if the amended or new claim is not substantially identical in scope relative to a previously issued claim, potential infringers of the amended/new claims are provided with an absolute and/or equitable intervening rights defense (35 U.S.C. § 252). For this reason, historically, patentees would rarely amend claims at the USPTO that were asserted in a co-pending litigation.
This calculus changed somewhat with the introduction of the post-grant trial proceedings of the America Invents Act (AIA).
For these reasons, amendment at the PTAB was sought in many of the earliest IPR filings. Since that time, however, patentees have reverted to old habits.
Note: The cumulative filing rate of petitions does not equal instituted trials (where amendments are possible). Yet, the number of petitions denied outright and or/settled prior to amendment does not alter the direction of the downtrend.
Critics will undoubtedly point to the strict requirements for motions to amend as driving their decreasing popularity. While that negative perception may have some impact on filing rates, as pointed out above, amendments are never a first option for highly valued patents. Likewise, many expired patents (or close to expiration) are being challenged at the PTAB. (Partly due to the fact that many older patents were not challengeable in an inter partes fashion under the old system, which required filing of the underlying patent application on or after 11/29/99) For expired, or soon to be expired patents, amendment is not feasible.
As discussed earlier this month, it is expected that requirements on motions to amend will be softened in the months ahead. Should the motion to amend requirements/page limits be adjusted going forward, perhaps some successful, contested amendments will drive an adjustment to the current downtrend.