This document contains final regulations providing guidance regarding the anti-cutback rules of section 411(d)(6) of the Internal Revenue Code, which generally protect accrued benefits, early retirement benefits, retirement-type subsidies, and optional forms of benefit under qualified retirement plans. The regulations address the limited circumstances under which a qualified retirement plan is permitted to be amended to eliminate or reduce early retirement benefits, retirement-type subsidies, or optional forms of benefit. The final regulations also provide related guidance concerning the notice requirements of section 4980F. These final regulations generally affect sponsors of, and participants in, qualified retirement plans.