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46 U.S. Code § 12502 - Identification numbers, signal letters, and markings

(a) For the identification of a vessel of the United States, the Secretary of Transportation—
shall maintain a unique numbering system and assign a number to each vessel of the United States;
may maintain a system of signal letters for a documented vessel;
shall record a name selected by the owner of a documented vessel approved by the Secretary as the vessel’s name of record; and
may establish other identification markings.
The manufacturer or owner of a vessel shall affix to the vessel and maintain in the manner prescribed by the Secretary the number assigned and any other markings the Secretary may require.
Once a number is assigned under this section, it may not be used by another vessel.
Once a documented vessel’s name is established, the name may not be changed without the approval of the Secretary.
A person may not tamper with or falsify a number or other marking required under this section.
Historical and Revision Notes

Revised section 12502

Subsection (a) of this section requires the Secretary to maintain a unique numbering system for vessels of the United States. The Secretary may use existing vessel numbering systems such as the hull identification number for this purpose, but must ensure that no two existing vessels of the United States have the same number. The Secretary should consider and propose the use of a 17-digit number to implement this requirement. This subsection also requires the Secretary to maintain a system of signal letters and to record vessel names for documented vessels. The Secretary is authorized to establish other vessel identification markings for vessels of the United States, such as hailing ports.

Subsections (b), (c), (d), and (e) contain other requirements and restrictions concerning vessel identification markings.

This section consolidates the requirements of sections 12114, 12115, 12116, and 12118 of title 46. For this reason, section 106 of this bill repeals those sections.

Statutory Notes and Related Subsidiaries
Effective Date

Section effective Jan. 1, 1989, with certain exceptions and qualifications, see section 107 of Pub. L. 100–710, set out as a note under section 31301 of this title.

Vessels Not Having Unique Number; Applicability of Provisions for Number Assignment

Pub. L. 100–710, title I, § 104(f), Nov. 23, 1988, 102 Stat. 4751, provided that:

Section 12502(a)(1) of title 46, United States Code (as enacted by section 101 of this Act), applies to a vessel of the United States that does not have a unique number as prescribed by the Secretary of Transportation under that section until the earlier of the following:
the next time the vessel is documented, numbered, or titled.
January 1, 1995.”