Taylor Swift Sued by Lucky 13 Apparel Company for Trademark Infringement—Get the Details ~ Entertainment News, Celebrity News, Celebrity Gossip

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It may be Taylor Swift 's favorite number, but it looks like the number 13 has landed the singer in hot water.

E! News has exclusively learned that the Grammy winner is being sued by Orange County-based apparel company Lucky 13.

According to the lawsuit, which was filed early Tuesday morning, the clothing brand is accusing T.Swift of trademark infringement stemming from her unauthorized use of Lucky 13's federally registered trademarks.

The company, which was founded in 1991 and specializes in cycles and street wear, claims that they have contacted Swift's camp numerous times but there was no resolution.

The "I Knew You Were Trouble" songstress has made no secret of the fact that the superstitious number plays a big role in her life.

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Not only is her birthday Dec. 13, but her Twitter handle includes the number as well.

She's also been spotted onstage with the number drawn on her hand during her many sold-out concerts.

"The significance of the number 13 on my hand … I paint this on my hand before every show because 13 is my lucky number— for a lot of reasons," she once explained to MTV News. "It's really weird."

"I was born on the 13th. I turned 13 on Friday the 13th. My first album went gold in 13 weeks. My first #1 song had a 13-second intro. Every time I've won an award I've been seated in either the 13th seat, the 13th row, the 13th section or row M, which is the 13th letter."

She added, "Basically whenever a 13 comes up in my life, it's a good thing."

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