The lawsuit alleges that the society has catnapped Bart and is "keeping Bart for publicity to raise money for the organization."
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"If we have to go to court, we have to go to court," Bart's owner, Ellis Hutson, told ABC Action News in Tampa before the lawsuit had been filed.
"I haven't done anything wrong, and I don't think it's right to take my cat."
Bart crawled his way into internet fame in January when he was found by neighbors five days after he had been buried alive. Hutson said he buried Bart because he believed him dead after Bart was hit by a car. Unable to afford veterinary bills, Huston turned to the Humane Society of Tampa Bay for help.
The Humane Society treated Bart for a broken jaw, open facial wounds and a ruined eye. They told ABC they hoped he'd be able to go home soon after surgery.
Then things got complicated. Sherry Silk, the director of the humane center, said she developed reason to believe that Hutson's home was not fit for the animal, saying Bart was knowingly buried alive. Because of this and other concerns, the society refused to send Bart home, so he now remains in the their care.
All parties say they just want what's best for the cat. There are two separate GoFundMe pages devoted to his care.
"Such a beautiful story, an amazing, amazing story, has turned into evil and greed," Hutson's neighbor, Dusty Albritton, told Action News.
Albritton also said she believes Bart should be returned to his owner.
The most recent update on Bart's condition was that he was doing great and able to eat.