Publications generally comply with the law, Mr. Höppner said, by referring to “the perpetrator  or, Mr. L.” But with such a well-known case, he said, expunging the record “is difficult to accomplish  and, morally speaking, rightly so.”

The court’s goals in the 1973 decision were laudable, he said, but the logic might not be workable in the Internet age, when archival material that was legally published at the time can be called up with a simple Google search. The question of excising names from archives has not yet been resolved by the German courts, he said.

Collisions in court involving free speech, the Internet and differing national laws are not new. In 2000, French courts fined Yahoo and ordered it to block access to auctions of Nazi memorabilia. The company fought the ruling in American courts, which upheld Yahoo on First Amendment grounds, but that decision was later overturned on jurisdictional grounds by the federal appeals court in San Francisco. Yahoo removed the auctions.

Michael Godwin, general counsel of the Wikimedia Foundation, a nonprofit organization in San Francisco, said the foundation “doesn’t edit content at all, unless we get a court order from a court of competent jurisdiction.”

The online encyclopedia is written and edited by armies of independent volunteers, and “if our German editors have chosen to remove the names of the murderers from their article on Walter Sedlmayr, we support them in that choice,” said Mr. Godwin, adding, “The English-language editors have chosen to include the names of the killers, and we support them in that choice.”

Wikipedians, as they call themselves, have removed or restricted information in the past. Wikipedia’s founder, Jimmy Wales, personally appealed to editors to keep off the site any information about the kidnapping of David Rohde, a Times reporter seized by the Taliban in Afghanistan, until his escape.

Mr. Godwin noted there were more than 12 million articles on Wikipedia and just 30 paid employees of the foundation, who largely maintain the software and run the computer servers. “We have one guy who handles legal complaints,” he said. “Me.” The idea that this small crew could police such vastness “does not scale,” he said.