It shouldn’t take a detective to realize that Sherlock Holmes is in the public domain by now, but apparently it takes a court to declare it.

We’ve covered the matter a couple of times. The Conan Doyle estate trademarked Holmes in the hope that could prevent others from using him without paying a licensing fee. A couple of years ago, the New York Times pointed out that some of the rights to Holmes are in kind of a twisted tangle.

But now a federal judge has issued a decision affirming that the characters and situations from all the Sherlock Holmes canon, save for the last story collection published after 1923, are definitely in the public domain within the USA and can be used by creators without paying licensing fees. Characters and situations from the last book are still off limits. (But then, that book is not generally considered to be Conan Doyle’s best work anyway.)

Chief Judge Rubén Castillo of the United States District Court of the Northern District of Illinois, Eastern Division, rejected the estate’s claim that the characters and the basic Holmes story line themselves remain under copyright, since they were not truly completed until Conan Doyle stopped writing. The judge did caution, however, that elements introduced in the 10 stories published after 1923 — such as the fact that Watson played rugby for Blackheath — remain protected.

The ruling was in response to a complaint filed by Leslie S. Klinger, the editor of a collected, annotated Holmes set and a number of other books about the detective. His publisher had declined to move forward with an anthology of new Holmes stories after the Conan Doyle estate said it would prevent the book from being sold unless Klinger paid a licensing fee.

The Conan Doyle estate may appeal, and insists that this does not affect any existing licensing agreements or its trademark claims. (I had thought there was some law saying that trademark claims couldn’t be applied against uses of public domain characters, but I can’t seem to find it now.)