CFR›Title 29›Subtitle B›Chapter XL›29 CFR Part 4001 Citation29 CFR Part 4001ContainsSections § 4001.1–§ 4001.3CorpusDaily eCFRDisplayed edition2026-10-21Last updated2026-10-21 PART 4001—TERMINOLOGY Sections § 4001.1 § 4001.1 Purpose and scope. § 4001.2 § 4001.2 Definitions. § 4001.3 § 4001.3 Trades or businesses under common control; controlled groups. Authority29 U.S.C. 1301, 1302(b)(3).Source61 FR 34010, July 1, 1996, unless otherwise noted.