CFR›Title 5›Chapter VIII›5 CFR Part 1840 Citation5 CFR Part 1840ContainsSection § 1840.1CorpusDaily eCFRDisplayed edition2026-08-05Last updated2026-08-05 PART 1840—SUBPOENAS Sections § 1840.1 § 1840.1 Service of subpoenas by mail. Authority5 U.S.C. 1212(e).