this subsection may be construed to limit any other authority of the Director. (i) Time for institution A petition for ex parte expungement may be filed, or the Director may institute on his own initiative an ex parte expungement proceeding, at any time following the expiration of three years after the date of registration. (j) Limitation on later ex parte expungement proceedings (1) No co-pending proceedings With respect to a particular registration, while an ex parte expungement proceeding is pending, no later ex parte expungement proceeding can be instituted with respect to the same goods or services that are the subject of a pending ex parte expungement proceeding. (2) Estoppel With respect to a particular registration, for goods or services previously subject to an instituted expungement proceeding for which, in that proceeding, it was determined that the registrant had used the mark for particular goods or services, as relevant, and the registration was not cancelled as to those goods or services, no further ex parte expungement proceedings may be initiated as to those goods or services, regardless of the identity of the petitioner. (k) Use in commerce requirement not altered Nothing in this section shall affect the requirement for use in commerce of a mark registered under section 1(a) or section 23. . (b) New grounds for cancellation Section 14 of the Trademark Act of 1946 ( 15 U.S.C. 1064 ) is amended— (1) by striking the colon at the end of paragraph (5) and inserting a period