That the mark whose use by a party is charged as an infringement was adopted without knowledge of the registrant’s prior use and has been continuously used by such party or those in privity with him from a date prior to (A) the date of constructive use of the mark established pursuant to
section 1057(c) of this title, (B) the registration of the mark under this chapter if the application for registration is filed before the effective date of the Trademark Law Revision Act of 1988, or (C) publication of the registered mark under subsection (c) of
section 1062 of this title:
Provided, however, That this defense or defect shall apply only for the area in which such continuous prior use is proved; or