Passing off someone else's witty tweets as your own in no laughing matter as Twitter is now taking down copied jokes, following a complaint filed by freelance writer, Olga Lexell: 

"I simply explained to Twitter that as a freelance writer I make my living writing jokes (and I use some of my tweets to test out jokes in my other writing). I then explained that as such, the jokes are my intellectual property, and that the users in question did not have my permission to repost them without giving me credit." 

Twitter obliged without any resistance. Like most other content hosting sites, Twitter is under the Digital Millennium Copyright Act (DMCA) and as such, provides 'safe harbour' from copyright claims as long as it doesn't protect infringing material. However, this usually pertains to tweets containing links to pirated/stolen/illegally hosted media, not for 140-character quips. Now, Lexell's precedent means anyone can submit their own complaint and keep the credit for their own wit.