ORS 830.770: Certificate of number required on boat; exceptions.

(1) A person may not operate a boat on the waters of this state, and an owner of a boat may not knowingly allow another person to operate the owner’s boat on the waters of this state, unless:

      (a) The owner of the boat holds a valid, effective certificate of number issued in the owner’s name as owner:

      (A) By this state, as provided in ORS 830.060 to 830.140 and 830.700 to 830.870;

      (B) By an agency of the federal government; or

      (C) By the state of principal use which issued the certificate of number under a federally approved numbering system.

      (b) The certificate of number is carried on the boat, except as provided in subsection (2) of this section.

      (2) Persons renting a boat from an operator of a boat livery are not required to carry the certificate of number on the boat, provided:

      (a) The operator of the boat livery retains the certificate of number at the livery office for immediate inspection by a peace officer;

      (b) The boat is clearly marked and identified as a livery boat; and

      (c) The boat operator has a signed rental or lease agreement containing the boat’s identifying number and the period of time for which the boat is rented or leased.