WICHITA — Earlier this year, TeeShirtMan owner Gary Butler didn't know what Twitter was.
Now, he's working on acquiring a trademark for the name.
"We had a lady come in that wanted to buy a Twitter shirt," Butler says.
"What is Twitter?" he asked his daughter.
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They looked at the microblogging site and checked into making Twitter T-shirts.
"The people who own it, believe it or not, forgot to register it with the United States patent office," Butler says.
No one with Twitter, which is based in San Francisco, returned e-mail requests for comment, though a representative did provide a link to Twitter's trademark policy.
Its guidelines state that no one should use the Twitter name without permission.