How do the filing date requirements differ for applications filed before December 18, 2013?
The filing date requirements for applications filed before December 18, 2013, were more stringent compared to those filed after this date due to the implementation of the Patent Law Treaties Implementation Act (PLTIA).
The MPEP states: For applications filed under pre-PLT (AIA) 35 U.S.C. 111 prior to December 18, 2013, a filing date is assigned to a nonprovisional application as of the date a specification containing a description and claim and any necessary drawings are filed in the U.S. Patent and Trademark Office (Office). See pre-PLT (AIA) 37 CFR 1.53(b).
(MPEP § 702)
This means that before December 18, 2013, a nonprovisional application required a specification with both a description and at least one claim, as well as any necessary drawings, to receive a filing date. This is in contrast to the more flexible requirements for applications filed on or after December 18, 2013, which can receive a filing date without claims or drawings (except for design applications).
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