Opinion of the Court
shown by clear expression or other affirmative steps taken to foster infringement, is liable for the resulting acts of infringement by third parties. We are, of course, mindful of the need to keep from trenching on regular commerce or discouraging the development of technologies with lawful and unlawful potential. Accordingly, just as Sony did not find intentional inducement despite the knowledge of the VCR manufacturer that its device could be used to infringe, 464 U.S., at 439, n. 19, mere knowledge of infringing potential or of actual infringing uses would not be enough here to subject a distributor to liability. Nor would ordinary acts incident to product distribution, such as offering customers technical support or product updates, support liability in themselves. The inducement rule, instead, premises liability on purposeful, culpable expression and conduct, and thus does nothing to compromise legitimate commerce or discourage innovation having a lawful promise.
III
A
The only apparent question about treating MGM’s evidence as sufficient to withstand summary judgment under the theory of inducement goes to the need on MGM’s part to adduce evidence that StreamCast and Grokster communicated an inducing message to their software users. The classic instance of inducement is by advertisement or solicitation that broadcasts a message designed to stimulate others to commit violations. MGM claims that such a message is shown here. It is undisputed that StreamCast beamed onto the computer screens of users of Napster-compatible programs ads urging the adoption of its OpenNap program, which was designed, as its name implied, to invite the custom of patrons of Napster, then under attack in the courts for facilitating massive infringement. Those who accepted StreamCast’s OpenNap program were offered software to perform the same services, which a factfinder could conclude
