37 C.F.R. § 6.4 Schedule for collective membership marks.
Title 37 - Patents, Trademarks, and Copyrights
All collective membership marks are classified as follows: [24 FR 10383, Dec. 22, 1959. Redesignated at 38 FR 14681, June 4, 1973]
Title 37: Patents, Trademarks, and Copyrights
PART 6—CLASSIFICATION OF GOODS AND SERVICES UNDER THE TRADEMARK ACT
§ 6.4 Schedule for collective membership marks.
------------------------------------------------------------------------Class Title------------------------------------------------------------------------ 200 Collective Membership. ------------------------------------------------------------------------

