An application for renewal must be filed within one year before the expiration date of the registration, or within the six-month grace period after the expiration date of the registration. If no renewal application is filed within this period, the registration will expire.
37 C.F.R. §2.182
Part 3 pertaining to both patents and trademarks is placed in the grouping pertaining to patents regulations.
Part 4 is placed in the separate grouping of parts pertaining to patents regulations.
Part 5 is placed in the separate grouping of parts pertaining to patents regulations.