The Neumuenster Zoo in northern Germany owns Knut's father, Lars, and said it is the legal owner of his first offspring - Knut - under a deal made with the Berlin Zoo, where the cub was born in 2006.
The Berlin Zoo has said it recognizes Neumuenster's ownership in principle, but maintains that does not give Neumuenster a right to any proceeds from the polar bear's huge success.
The irresistibly cute Knut - raised by hand in Berlin after his mother rejected him at birth - became a media phenomenon in early 2007.
The Berlin Zoo reported a 27 percent increase in visitors last year compared with 2006 and had a 2007 profit of nearly $10.7 million. It has licensing agreements for all kinds of Knut products, including stuffed animals, T-shirts, mugs and DVDs.
Neumuenster Zoo director Peter Druewa said in a statement that his zoo had unsuccessfully tried to negotiate with the Berlin Zoo but has now turned to a court in Berlin for a ruling.
"We do not want to remove Knut from his environment," Druewa said. "But we have a right to our request for money."
