Copyright- Statute of limitations
An exclusive license is identical to ownership for the purpose of the Copyright statute of limitations, which runs from the time that the initial licensee is aware of the primary infringement; the clock is not restarted by each attendant infringement.
http://www.ca2.uscourts.gov/decisions/isysquery/fb6e4ccb-6ffa-40f1-b0a8-b38f555365b5/1/doc/14-3106_opn.pdf#xml=http://www.ca2.uscourts.gov/decisions/isysquery/fb6e4ccb-6ffa-40f1-b0a8-b38f555365b5/1/hilite/
Since 2011. An occasional commonplacing of the U.S. Circuit Courts of Appeal.
Neither an authoritative statement of the law nor legal advice. Quick work.