The DEFEND IP Act would create a legal mechanism for copyright owners to combat foreign websites engaged in digital piracy. Copyright holders could petition federal district courts to designate foreign websites as "foreign digital piracy sites" if those sites are primarily used for copyright infringement and likely to cause irreparable harm to the copyright owner. Once designated, copyright holders could then petition courts to order internet service providers and domain name services to block U.S. users' access to these sites, provided the burden on service providers is not excessive and no less restrictive alternatives exist. ISPs would receive broad legal immunity for good-faith compliance efforts and could recover reasonable compliance costs from those seeking the orders. The bill would also enable courts to compel payment processors, internet service providers, and ad networks to cease business with designated piracy platforms.