A 102(g) Rejection requires that the invention be reduced to practice. However, 102(a) says that if an invention is "known or used in this country" it can't be patented. So wouldn't a reduce to practice invention trigger the used by other clause in 102(a)? Is an Ex Parte 102(g) Rejection only when the office misses prior art and someone tells them to double check?
(My question is for PRE-AIA)
Pre-AIA, when it was "first to invent", there needed to be a scheme to figure out who won that contest. It was essentially, first to conceive as long as the first conceiver proceeded diligently from conception to reduction to practice. Person A might reduce to practice (which can be accomplished by filing an enabling application) first, but lose to person B who filed later, but who conceived earlier. But if person B conceived before A and could prove diligent effort towards reduction to practice from a date before A's conception, B would be the first to invent. B not working on it during a one week vacation might knock out person B's chances.
Also, someone actually reducing it to practice would not make it prior art leading to a 102(a) rejection for someone else as long as the invention was kept confidential and not offered for sale.
