Google says that it has already taken down “hundreds of pages” with images that obviously violate the court ruling, when Mr. Mosley has requested that it do so, but that there are many cases in which it is not immediately clear whether the content is affected by the ruling, and that in those cases a judge or other competent official should make the decision. And the company said it has never created such a filter on behalf of one person.

It cites French and E.U. law, which do not require search engines to comb the Web for unlawful content, and argues that, in any case, many hits the photos receive are driven by communications among individuals, so blocking them on search would not end the problem.

A concurrent case, at the European level, would appear to back Google, though lawyers in the case say it might not be directly relevant. The European Court of Justice, which is based in Luxembourg, is currently examining a Spanish man’s claim of a “right to be forgotten” on the Web — something Silicon Valley companies oppose.

In a sign that the case might be swinging the technology giants’ way, Niilo Jaaskinen, the Finnish lawyer who serves as advocate general of the court, issued an opinion in June that search engines were not responsible “for personal data appearing on Web pages they process.”

E.U. data protection law “does not entitle a person to restrict or terminate dissemination of personal data that he considers to be harmful or contrary to his interests,” Mr. Jaaskinen wrote. Though the court is not bound by the advocate general’s opinion, it often follows his recommendations. It has yet to decide the matter.

Why would Mr. Mosley seek action against an American company in a French court for actions committed in Britain by a now-defunct English newspaper? It might have to do with France’s strict privacy laws, which make it a criminal offense to record another person — image or sound — in a private space without the person’s consent.

His lawyer, Clara S. Zerbib, said that it was because a Paris court had ruled in 2011 that the recording of the News of the World pictures, without Mr. Mosley’s knowledge in a private place, had been illegal and that a judge might thus find that distributing such pictures on the Internet was also illegal. She noted that Mr. Mosley also worked in France as president of the International Automobile Federation, the Paris-based governing body of Formula One racing, and was concerned about his reputation there.