Twitter recently amended its Web site terms of use to emphasize that users own their own postings. The changes still grant Twitter a broad license to use Tweets. Twitter’s terms also permit others to publish user’s Tweets via the Twitter API. While guidelines for the API are still being developed, they will likely include a requirement that when a user republishes a Tweet via the Twitter API, he/she identifies the author of the Tweet, does not edit the Tweet, and obtains permission prior to using the Tweet in a commercial product (such as a book, poster or t-shirt). The terms also “leave the door open for advertising” by indicating to users that the company and its partners may place advertising on the site in connection with user-submitted posts.

TIP: Based on Twitter’s policy, it seems that Tweets may be republished without permission on Web sites and other online means via the Twitter API, but the new rules don’t seem to clarify whether Tweets can be used for traditional advertising functions (e.g., for use in a print ad).