This subpart applies to each vessel equipped with propulsion machinery of any type used on waters subject to the jurisdiction of the United States and on the high seas beyond the territorial seas for vessels owned in the United States except:

(a) Foreign vessels temporarily using waters subject to U.S. jurisdiction;

(b) Military or public vessels of the United States, except recreational-type public vessels;

(c) A vessel whose owner is a State or subdivision thereof, which is used principally for governmental purposes, and which is clearly identifiable as such;

(d) Ships' lifeboats;

(e) A vessel which has or is required to have a valid marine document as a vessel of the United States.

Where the Coast Guard issues numbers, the following classes of vessels are exempt, under Section 12303 of Title 46, United States Code, from the numbering provisions of Sections 12301 and 12302 of Title 46, United States Code, and this part:

(a) A vessel that is used exclusively for racing.

(b) A vessel equipped with propulsion machinery of less than 10 horsepower that:

(1) Is owned by the owner of a vessel for which a valid certificate of number has been issued;

(2) Displays the number of that numbered vessel followed by the suffix “1” in the manner prescribed in § 173.27; and

(3) Is used as a tender for direct transportation between that vessel and the shore and for no other purpose.

(a) Except as provided in § 173.17, no person may use a vessel to which this part applies unless:

(1) It has a number issued on a certificate of number by the issuing authority in the State of principal operation; and

(2) The number is displayed as described in § 173.27.

(b) This section does not apply to a vessel for which a valid temporary certificate has been issued to its owner by the issuing authority in the State of principal operation.

(a) Section 12302(c) of Title 46, United States Code, states:

(b) Section 12302(d) of Title 46, United States Code, states:

No person may operate a vessel to which this part applies that has any number that is not issued by an issuing authority for that vessel on its forward half.

(a) Except as provided in §§ 173.13 and 173.17, no person may operate a vessel to which this part applies unless they have on board in hard copy or digital form:

(1) A valid certificate of number or temporary certificate for that vessel issued by the issuing authority in the State in which the vessel is principally operated; or

(2) For the vessel described in paragraph (b) of this section, a copy of the lease or rental agreement, signed by the owner or his or her authorized representative and by the person leasing or renting the vessel, that contains at least:

(i) The vessel number that appears on the certificate of number; and

(ii) The period of time for which the vessel is leased or rented.

(b) Section 12304(a) of Title 46, United States Code, states in part: The certificate of number for a vessel less than 26 feet in length and leased or rented to another for the latter's noncommercial operation of less than 7 days may be retained on shore by the vessel's owner or representative at the place from which the vessel departs or returns to the possession of the owner or the owner's representative.

Each person operating a vessel to which this part applies shall present the certificate or lease or rental agreement required by § 173.21 to any Federal, State, or local law enforcement officer for inspection at his or her request.

No person may operate a vessel to which this part applies unless the certificate or lease or rental agreement required by § 173.21 is carried on board in such a manner that it can be handed to a person authorized under § 173.23 to inspect it.

(a) Each number required by § 173.15 must:

(1) Be painted on or permanently attached to each side of the forward half of the vessel except as allowed by paragraph (b) or required by paragraph (c) of this section;

(2) Be in plain vertical block characters of not less than 3 inches in height;

(3) Contrast with the color of the background and be distinctly visible and legible;

(4) Have spaces or hyphens that are equal to the width of a letter other than “I” or a number other than “1” between the letter and number groupings (Example: DC 5678 EF or DC-5678-EF); and

(5) Read from left to right.

(b) When a vessel is used by a manufacturer or by a dealer for testing or demonstrating, the number may be painted on or attached to removable plates that are temporarily but firmly attached to each side of the forward half of the vessel.

(c) On vessels so configured that a number on the hull or superstructure would not be easily visible, the number must be painted on or attached to a backing plate that is attached to the forward half of the vessel so that the number is visible from each side of the vessel.

(d) Each number displayed on a tender exempted under § 173.13 must meet the requirements of paragraph (a) of this section and have a space or hyphen that is equal to the width of a letter other than “I” or a number other than “1” between the suffix and the number. (Example: DC 5678 EF 1 or DC-5678-EF-1.)

A person whose name appears as the owner of a vessel on a certificate of number shall, within 15 days, notify the issuing authority in a manner prescribed by the issuing authority of:

(a) Any change in his or her address;

(b) The theft or recovery of the vessel;

(c) The loss or destruction of a valid certificate of number;

(d) The transfer of all or part of his or her interest in the vessel; and

(e) The destruction or abandonment of the vessel.

A person whose name appears as the owner of a vessel on a certificate of number shall surrender the certificate in a manner prescribed by the issuing authority within 15 days after it becomes invalid under paragraph (b), (c), (d), or (e) of § 173.77.

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:

(a) The vessel is documented by the Coast Guard;

(b) The certificate of number is invalid under paragraph (c) of § 173.77; or

(c) The vessel is no longer principally operated in the State where the certificate was issued.

No person may operate a vessel except a vessel exempted in § 173.13 that has a number issued by the Coast Guard unless it has the validation sticker issued with the certificate of number displayed within 6 inches of the number.