(a) General. This part establishes procedures under which a plan sponsor shall request the PBGC to approve a plan amendment under
section 4220 of ERISA. This part applies to all multiemployer plans covered by title IV of ERISA that adopt amendments pursuant to the authorization of
sections 4201-4219 of ERISA (except for amendments adopted pursuant to
section 4211(c)(5)). (The covered amendments are set forth in
paragraph (b) of this section.) The subsequent modification of a plan amendment adopted by authorization of those sections is also covered by this part. This part does not, however, cover a plan amendment that merely repeals a previously adopted amendment, returning the plan to the statutorily prescribed rule.