Twitter Inc., which made news for having only nine patents at the time of its initial public offering in November, agreed to purchase 900 patents from International Business Machines Corp. The purpose of this deal is to obtain access to new technology and to begin to build an intellectual property portfolio that will serve as a defense for Twitter against infringement suits. The agreement between Twitter and IBM was signed in December and announced Jan. 31. It also resolves a dispute between the two companies that began when IBM wrote to Twitter last year about possible infringement of three of its patents.

"This acquisition of patents from IBM and licensing agreement provide us with greater intellectual property protection and give us freedom of action to innovate on behalf of all those who use our service," Ben Lee, Twitter's legal director, said in a joint statement with IBM, according to Reuters.

IBM has received the most U.S. patents of any company for 21 years in a row, according to Businessweek. The company has a history of making similar deals with other technology firms whose patent portfolios are rather slim. It sold patents to Google that helped the company construct defenses in lawsuits over smartphone-related intellectual property, and sold patents to Facebook that helped to settle a suit with Yahoo! Inc.