Andrea Plunket was the wife of Sheldon Reynolds who owned the Holmes copyright in the US during the 1950's and produced the Ron Howard version of Sherlock Holmes. However the copright later passed over to Andrea Plunket. It seems that Warners received permission from Andrea Plunket to make their big budget series starring Robert Downey Jnr as Sherlock Holmes, but the BBC have made no such requests.
Mrs Plunket is now throwing down a legal gauntlet to the BBC. She insists she retains the copyright to the last ten stories from the Conan Doyle oeuvre in the U.S. More crucially, she claims to have registered as her trademark all the leading characters in the Sherlock Holmes stories and accuses the BBC of breaching her trademark.
And from the NEW YORK TIMES