See "A publication in my profile doesn’t belong to me" in https://help.researchgate.net/hc/en-us/articles/14292798510993-Authorship for instructions how to remove publications from your profile. This is a frequent problem in ResearchGate, caused by an automated algorithm.
Insteresting and useful article, Wolfgang. Thanks. Unfortunately, there are people who use ResearchGate to promote themselves improperly. And the statement in the article: 'If another researcher has claimed your publication, it is usually the result of an honest mistake.' is not always true. I recently published two cases of improper appropriation in a Letter to the Editor (https://www.researchgate.net/publication/374089045_Coauthorship_Substitution_in_Virtual_Scientific_Repositories).