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17 U.S. Code § 904 - Duration of protection

The protection provided for a mask work under this chapter shall commence on the date on which the mask work is registered under section 908, or the date on which the mask work is first commercially exploited anywhere in the world, whichever occurs first.
Subject to subsection (c) and the provisions of this chapter, the protection provided under this chapter to a mask work shall end ten years after the date on which such protection commences under subsection (a).
All terms of protection provided in this section shall run to the end of the calendar year in which they would otherwise expire.