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Clean your twitter history and prevent them being archived

Did you know that the Library of Congress archives all undeleted tweets that are 6 months or older? After that they will then be stored forever!
http://1.usa.gov/yGw3DO

By the way, “deleted tweets” will not be part of the archive; however, if you delete a tweet AFTER it has already been archived by the Library of Congress, that tweet will STILL remain archived. Even though it is deleted from Twitter, it will still show up, in perpetuity in the Library of Congress.
http://blogs.loc.gov/loc/2010/04/the-library-and-twitter-an-faq/

Download Tweet Cleaning App and delete your old tweets before Library of Congress archives them

https://itunes.apple.com/app/id807175980