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“It’s extraordinarily difficult to claim everything within 25 claims — you would’ve lost subject matter,” said Monroy. “When you look at the complexities of the biotech inventions, it’s very difficult to do that.”

Cacheris wrote that the new rules would be a “drastic departure from the terms of the Patent Act as they are presently understood.” He also wrote that a provision that would have allowed patent seekers to exceed the 25-claim limit only if they provide extensive research to the examiner would unfairly shift the burden off the PTO and onto the applicant.

Patent lawyers are watching closely to see how the ruling affects the patent office’s efforts to implement new rules in the future. The office is moving forward with other, so-called information disclosure statement rule changes, which patent lawyers say is also an attempt to shift some of the burden of examination onto the applicant.

“It will be interesting to see what effect this will have on the USPTO’s other rules going forward,” said Townsend’s Apple.