Superstar Taylor Swift is being sued for her love of the number 13.

All Swifties know that the singer absolutely loves the number, and even considers it a good luck charm. For a long time, she wrote it on her hand for every single concert; it's part of her Twitter handle, and her management company is called 13 Management, LLC.

Unfortunately, Orange County-based apparel company Lucky 13 doesn't like that. E! Online reports the lawsuit was filed early Tuesday morning accusing the 'Red' hitmaker of trademark infringement, claiming she used the company's federally registered trademarks without authorized use.

Apparently, she used the phrase 'Lucky 13' on t-shirts, selling them in her online store, and Robert Kloetzly, owner, wants her to stop.

Not only does he want her to stop, he wants to get her online store shut down and is seeking to obtain the profits she's made from the shirts or damages paid to the company -- whichever is a greater sum of money.

Kloetzly, per EW, describes Swift as "a tatted up singer who likes fast cars and dangerous men who drive them inappropriately." He also claims her 'I Knew You Were Trouble' music video could be mistaken for a Lucky 13 advertisement.

Of course Swift actually doesn't have a tattoo and has no desire to get one.

She has been vocal about her love for 13 over the years, telling MTV News, "I was born on the 13th. I turned 13 on Friday the 13th. My first album went gold in 13 weeks. My first No. 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." Adds Swift, "Basically whenever a 13 comes up in my life, it's a good thing."

Well ... until now, that is. Hopefully the matter will be resolved quickly and Swift can continue seeing 13 pop up in her life in all sorts of magical ways.