How does a terminal disclaimer affect patent term?
A terminal disclaimer affects the patent term by disclaiming the terminal part of the statutory term of a patent, which would extend beyond the expiration date of an earlier patent or application. This effectively shortens the enforceable term of the later patent to expire at the same time as the earlier patent.
According to the MPEP: The patentee has reduced the patent’s statutory term by effectively eliminating the disclaimed portion from the original patent, by operation of 35 U.S.C. 253 (which indicates that a disclaimer of patent claims “shall thereafter be considered as part of the original patent” and such applies to disclaimers of patent term).
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