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On-Again, Off-Again Inventorship, PTAB Litigation Blog

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Deciding who invented patents can be “one of muddiest concepts in the muddy metaphysics of the patent law.” Mueller Brass Co. v. Reading Industries, Inc., 352 F. Supp. 1357, 1372 (E.D. Pa. 1972).  But identifying who contributed what, and most importantly, when they made those contributions, has profound strategic consequences for potentially invalidating prior art.  So when a patent owner changes its mind about who the inventors are to try to get behind prior art, can it ever just ask to go back to the way things were when its strategic interests change?

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