17 U.S. Code § 907 - Limitation on exclusive rights: innocent infringement
(a) Notwithstanding any other provision of this chapter, an innocent purchaser of an infringing semiconductor chip product—
(1) shall incur no liability under this chapter with respect to the importation or distribution of units of the infringing semiconductor chip product that occurs before the innocent purchaser has notice of protection with respect to the mask work embodied in the semiconductor chip product; and
(b) The amount of the royalty referred to in subsection (a)(2) shall be determined by the court in a civil action for infringement unless the parties resolve the issue by voluntary negotiation, mediation, or binding arbitration.
(c) The immunity of an innocent purchaser from liability referred to in subsection (a)(1) and the limitation of remedies with respect to an innocent purchaser referred to in subsection (a)(2) shall extend to any person who directly or indirectly purchases an infringing semiconductor chip product from an innocent purchaser.