33 C.F.R. § 173.33
The person whose name appears on a certificate of number as the owner of a vessel shall remove the number and validation sticker from the vessel when:
[CGD 72-54R, 37 FR 21399, Oct. 7, 1972, as amended by USCG-2003-14963, 77 FR 18700, Mar. 28, 2012]