We study how the strength of public intellectual property rights (IPR) protection against software piracy (copyright protection) affects private IPR protection (that software developers may themselves undertake to protect their IPR). There are two software developers that offer a product variety of differing (exogenously given) quality and compete in prices for heterogeneous users, who make a choice whether to buy a legal version, use an illegal copy (if they can), or not use a product at all.