Twitter on Monday filed official papers to acquire third-party desktop publishing firm TweetDeck for $40 million in cash and stock.

Rumors of the upcoming deal have circulated for weeks as Twitter continues on their path to reign in third-party developers before they can develop an increasing amount of influence over the microblogging site.

Twitter has also become wary of third-party developers over the last several months as their own ad strategy has begun to emerge and many third party desktop and mobile apps have allowed users to avoid those strategies.

The acquisition is not the first from Twitter, they purchased the iPhone App “Tweetie” and they partnered with photo service TwitPic when launching their new interface for their mobile app.

Purchasing TweetDeck was seen by some analysts as a necessity when UberMedia made an offer to the company which would have given them a very large bargaining chip in regards to future Twitter matters, a scenario Twitter needed to avoid to retain full control over their own practices. UberMedia already controls the popular Twitter apps, UberSocial and Twidroyd.