IBM's the biggest patent holder of all time, and when it comes to defending them, it tries to work things out amicably. That's exactly what's happened with Twitter, after the social giant today announced it has bought 900 patents from Big Blue and entered into a cross-licensing agreement to limit the threat of future lawsuits. The move comes after IBM accused Twitter of infringing three of the company's patents concerning: "efficient retrieval of uniform resource allocators," "presenting advertising in an interactive service" and "programmatic discovery of common contacts." IBM noted at the time that it would rather talk it out instead of lawyering up, while Twitter claimed it could defend itself against IBM's allegations. Thankfully, it didn't move from the boardroom to the courtroom and the two parties have signed a deal that will provide Twitter with "greater intellectual property protection" and "freedom of action to innovate," meaning it's business as usual for users.