Quidditch, a sport created for the fictional world of Harry Potter before spreading to US college campuses, is changing its name to quadball.

In December, two of the sport’s major governing bodies, US Quidditch and Major League Quidditch, said they were considering a name change due to “sponsorship and broadcast opportunities” that had been lost because Warner Bros, which produces the Harry Potter film series, owns the copyright for the sport’s present name.

However, on Tuesday another of the sport’s governing bodies, the International Quidditch Association, cited JK Rowling’s “anti-trans positions” as a reason for the change.

The Harry Potter author has been accused of being transphobic, an allegation she denies.

“We’ve tried to be clear that it’s both reasons,” Jack McGovern, a spokesman for US Quidditch and Major League Quidditch, told the New York Times.

“We did not intend to give a value judgment about which reason was more important than the other.”

He added that the sport’s association with Rowling had created a problem in recruiting new players.

Major League Quidditch and US Quidditch will now be known as Major League Quadball and US Quadball respectively. The International Quidditch Association is expected to change its name in the near future.

“In less than 20 years, our sport has grown from a few dozen college students in rural Vermont to a global phenomenon with thousands of players, semi-pro leagues and international championships,” Mary Kimball, the executive director of US Quadball, said in a statement.

“Our organizations are committed to continuing to push quadball forward.”

The sport’s new name refers to the number of balls on the field during games, as well as the number of player positions. The fictional game was adapted into a real-life sport in 2005 and now has 600 teams in 40 countries.