We develop a model to investigate the manner in which the pricing, profitability, and protection strategies of a seller of a proprietary digital good respond to changing market conditions. Specifically, we investigate how product piracy and the presence of open source software alternatives (such as Open Office) impact the optimal strategy of a seller of proprietary software (such as Microsoft Office). In contrast to previous literature, we show that firms may make more (rather than less) effort to control piracy when network externalities are strong. In addition, we show that the level of network externalities amplifies losses incurred by an incumbent due to high-quality pirated goods. Therefore, for products characterized by high network e...