Third-party ad networks have been officially banned from Twitter, according to a post on the Twitter blog on Monday from Chief Operating Officer Dick Costolo. It's a move that could drive some of the advertising start-ups that have built around Twitter out of business.
"We will not allow any third party to inject paid tweets into a timeline on any service that leverages the Twitter API," the post read, explaining that the exception will be Twitter's own "promoted tweets" program that it announced earlier this year.
But the straight story is that these third-party networks--include Adly and the just-launched TweetUp--now compete with Twitter itself for advertising dollars.
For more of this story, read Twitter cuts the cord on third-party ad networks on CNET News.