CAFC in GIACOMINI : provisionals offensive weapons under 102(e)

The CAFC in GIACOMINI noted:

Treating a provisional application’s filing date
as both the patent’s priority date and its effective refer-
ence date does not raise the alleged tension between
sections 102(e) and 119.

At issue was the prior art effect of a patent application
for which the nonprovisional was filed after the patent
application at issue, but the provisional of the prior art
was filed before the patent application at issue.
The CAFC found the prior art defeating.

Previously, the BPAI had reached the same conclusion:


Yamaguchi: provisional can be prior art as of its filing date

**See Federal Circuit: Provisional Application Can Show Another Party Was First to Invent which portrays this as "first to invent" vs. "first to file":

The U.S. patent system is based on the "first to invent" doctrine, which awards patents to the first party to "reduce to practice" an invention. That means actually or constructively creating an embodiment of the invention. Most other countries use the "first to file" system, which awards patents to the party who files the application first.

Of course, in this case, the inventor of the applied prior art was the "first to file."