Subject to subsection (a), protection is available under this chapter to any mask work that was first commercially exploited on or after July 1, 1983, and before the date of the enactment of this chapter, if a claim of protection in the mask work is registered in the Copyright Office before July 1, 1985, under section 908.

In the case of any mask work described in paragraph (1) that is provided protection under this chapter, infringing semiconductor chip product units manufactured before the date of the enactment of this chapter may, without liability under sections 910 and 911, be imported into or distributed in the United States, or both, until two years after the date of registration of the mask work under section 908, but only if the importer or distributor, as the case may be, first pays or offers to pay the reasonable royalty referred to in section 907(a)(2) to the mask work owner, on all such units imported or distributed, or both, after the date of the enactment of this chapter.

In the event that a person imports or distributes infringing semiconductor chip product units described in paragraph (2) of this subsection without first paying or offering to pay the reasonable royalty specified in such paragraph, or if the person refuses or fails to make such payment, the mask work owner shall be entitled to the relief provided in sections 910 and 911.