Tex. Transportation Code § 503.024

(a) A person is not required to obtain a dealer general distinguishing number if the person:

(1) sells or offers to sell during a calendar year fewer than five vehicles of the same type that are owned and registered in that person's name; or

(2) is a federal, state, or local governmental agency.

(b) For the purposes of Section 503.021, a person is not engaging in business as a dealer by:

(1) selling or offering to sell, if the sale or offer is not made to avoid a requirement of this chapter, a vehicle the person acquired for personal or business use to:

(A) a person other than a retail buyer if not sold or offered through a licensed auctioneer; or

(B) any person if the sale or offer is made through a licensed auctioneer;

(2) selling, in a manner provided by law for the forced sale of vehicles, a vehicle in which the person holds a security interest;

(3) acting under a court order as a receiver, trustee, administrator, executor, guardian, or other appointed person;

(4) selling a vehicle the person acquired from the vehicle's owner as a result of paying an insurance claim if the person is an insurance company;

(5) selling an antique passenger car or truck that is at least 25 years of age; or

(6) selling a special interest vehicle that is at least 12 years of age if the person is a collector.

(c) For the purposes of Section 503.021, a domiciliary of another state who holds a dealer license and bond, if applicable, issued by the other state is not engaging in business as a dealer by:

(1) buying a vehicle from, selling a vehicle to, or exchanging a vehicle with a person who:

(A) holds a general distinguishing number issued by the department, if the transaction is not intended to avoid a requirement of this chapter; or

(B) is a domiciliary of another state who holds a dealer license and bond, if applicable, issued by the other state and the transaction is not intended to avoid a requirement of this chapter; or

(2) buying, selling, including by consignment, or exchanging at a public auction:

(A) an antique vehicle that is at least 25 years of age; or

(B) a special interest vehicle that:

(i) is at least 12 years of age; or

(ii) has been the subject of a retail sale.

(d) For the purposes of Section 503.021, a licensed auctioneer is not engaging in business as a dealer by, as a bid caller, selling or offering to sell property, including a business that holds the title to any number of vehicles, to the highest bidder at a bona fide auction if:

(1) legal or equitable title does not pass to the auctioneer;

(2) the auction is not held to avoid a requirement of this chapter; and

(3) for an auction of vehicles owned legally or equitably by a person who holds a general distinguishing number, the auction is conducted at the location for which the general distinguishing number was issued.

(e) In this section, "special interest vehicle" has the meaning assigned by Section 683.077(b).