20 years is a good first approximation for patent term.
Patents expire 20 years from the first non-provisional priority date in the US, plus whatever term extension is granted by the USPTO to compensate you for USPTO delays, less any term lost for a terminal disclaimer.
It's fair game to sue on an expired patent, because in some cases, you can collect for past damages that accrued up to six years in the past. That's probably why the complaint focused on an older product, potentially sold during the patent term.
It's fair game to sue on an expired patent, because in some cases, you can collect for past damages that accrued up to six years in the past. That's probably why the complaint focused on an older product, potentially sold during the patent term.