Impax Laboratories announced that it has reached an agreement with Purdue Pharma to settle all outstanding patent litigation surrounding Impax’s generic version of the reformulated OxyContin that is now on the market.

In a statement, Impax said will have the right to market a specified number of bottles of its generic OxyContin under the agreement’s terms, though that is contingent on the company getting final approval from the FDA on its Abbreviated New Drug Application (ANDA) for the drug. If Impax does not receive final ANDA approval for its generic version, it will still have the right to launch a specified number of bottles of an authorized generic version of OxyContin. In either case, the start date will be Jan. 1, 2016.

IMS Health data put US sales of OxyContin at approximately $2.6 billion for the 12 months ended September 2013.