Comment by GuB-42

6 days ago

In Europe, Tintin is under copyright until 2053 (death + 70 years).

And the rightsholders (Tintinimaginatio, previously Moulinsart) are very aggressive about it, even more so than Disney. They don't have the lobbying power of Disney, but they are going to do everything in their power to protect and possibly overstep their rights. It includes using trademark laws and publishing new Tintin adventures against the will of the original author as an attempt to renew their copyright.

If he sold his rights then it's not really against his wishes anymore.