3

You keep all the priority dates. Upon reinstatement, everything is reinstated. It can have an effect on Patent Term Extension.


2

You need not do anything. It will become abandoned by your failure to reply in time (37 CFR 1.135(a)). Nevertheless, if you want, you can expressly abandon your application by filing a letter to this effect (37 CFR 1.138). However, if you do this, there's little chance of reviving it later. It would therefore be a pretty rare case that this is a good idea, ...


2

"Can I just reapply for the same idea?" Yes, but you will lose the original priority date. To try to keep the original filing date you may be able to revive the application.


1

There is not a strict limit (other than 20 years after the priority date) but the USPTO gives a petition to revive greater scrutiny after 1 year. Even if a petition to revive is granted by the Office, it is still subject to be brought up in court later in an attack in the validity of the resolution patent. See quote from the MPEP below. 37 CFR 1.137 ...


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