37 CFR § 2.42 - Concurrent use.
(a) Prior to seeking concurrent use, an application for registration on the Principal Register under the Act must assert use in commerce and include all the application elements required by the preceding sections, in addition to § 2.44 or § 2.45, if applicable.
(b) The applicant must also include a verified statement that indicates the following, to the extent of the applicant's knowledge:
(1) For a trademark or service mark, the geographic area in which the applicant is using the mark in commerce; for a collective mark or certification mark, the geographic area in which the applicant's members or authorized users are using the mark in commerce;
(2) For a trademark or service mark, the applicant's goods or services; for a collective trademark, collective service mark, or certification mark, the applicant's members' or authorized users' goods or services; for a collective membership mark, the nature of the applicant's collective membership organization;
(3) The mode of use for which the applicant seeks registration;
(4) The concurrent users' names and addresses;
(5) The registrations issued to or applications filed by such concurrent users, if any;
(6) For a trademark or service mark, the geographic areas in which the concurrent user is using the mark in commerce; for a collective mark or certification mark, the geographic areas in which the concurrent user's members or authorized users are using the mark in commerce;
(7) For a trademark or service mark, the concurrent user's goods or services; for a collective trademark, collective service mark, or certification mark, the concurrent user's members' or authorized users' goods or services; for a collective membership mark, the nature of the concurrent user's collective membership organization;
(8) The mode of use by the concurrent users or the concurrent users' members or authorized users; and
(9) The time periods of such use by the concurrent users or the concurrent users' members or authorized users.
(c) For the requirements to amend an application to concurrent use, see § 2.73.
(d) For the requirements of a concurrent use proceeding, see § 2.99.