49 CFR §374.403

1. (a)All motor carriers of passengers and baggage subject to 49 U.S.C. subtitle IV, part B, which provide in their tariffs for the declaration of baggage in excess of a free baggage allowance limitation, shall provide clear and adequate notice to the public of the opportunity to declare such excess value on baggage.
2. (b)The notice referred to in paragraph (a) of this section shall be in large and clear print, and shall state as follows:
3. (c)The notice referred to in paragraphs (a) and (b) of this section shall be (1) placed in a position near the ticket seller, sufficiently conspicuous to apprise the public of its provisions, (2) placed on a form to be attached to each ticket issued (and the ticket seller shall, where possible, provide oral notice to each ticket purchaser to read the form attached to the ticket), (3) placed in a position at or near any location where baggage may be checked, sufficiently conspicuous to apprise each passenger checking baggage of its provisions, and (4) placed in a position at each boarding point or waiting area used by the carrier at facilities maintained by the carrier or its agents, sufficiently conspicuous to apprise each boarding passenger of the provisions of the said notice.