The heirs of Tintin author Herge on Wednesday said they would launch a legal challenge to a Dutch court decision that they do not own all the rights to the boy reporter's image.
A court in The Hague ruled in May in favour of a small Dutch fanclub that had been sued in 2012 by Moulinsart SA, the Belgium-based company that manages the lucrative Tintin business, for publishing extracts in their fanzine.
Moulinsart exercises tight control over the rights and licensing to ginger-quiffed teen Tintin, his dog Snowy, Captain Haddock, Thomson and Thompson, and other characters from the comic book adventures.
"Moulinsart intends to exercise every legal avenue open to it under Dutch law," said the company led by Herge's widow, Fanny Rodwell, and her new husband Nick Rodwell, in a joint statement with Tintin publisher Casterman.
"We intend to take the case to the Supreme Court of the Netherlands," Alain Berenboom, the Belgian lawyer for Moulinsart, told AFP.
The Dutch court's surprise judgment upheld the right of the "Herge Society" in the Netherlands to print extracts from Tintin.
It said that a 1942 document showed that Herge gave publishing rights for the Tintin books to Casterman, meaning that Moulinsart itself cannot decide who can use material from the books.
The document came from a Herge expert who wishes to remain anonymous, and its validity has not been contested by Moulinsart.
Herge's heirs said the court "appears to have fallen into confusion" over the rights held by Moulinsart and Casterman, adding that they were "astonished" by the judgment.
Moulinsart said they recognised that Herge had given worldwide publishing rights to Casterman for the Adventures of Tintin books, but insisted that "all the other rights remain the property of Herge" including drawings from the books.
Herge -- whose real name was Georges Remi and whose pen name comes from reading his initials backwards in French -- died in 1983.