Harry Potter and the Goblet of Fire is the fourth book in the series
The publisher of the Harry Potter series has denied a claim that author JK Rowling stole the idea for one of her books from another writer.
Lawyers for the estate of late author Adrian Jacobs are suing Bloomsbury Publishing PLC.
They claim Harry Potter and the Goblet of Fire reproduces substantial parts of Jacobs's story The Adventures of Willy the Wizard.
Bloomsbury described the claim as "unfounded and untrue".
Ms Rowling made no comment.
A statement on the website of law firm DMH Stallard, which is representing the claimant, confirmed the estate was taking Bloomsbury to court for copyright infringement.
Bloomsbury said the claim was baseless and the book "will be defended vigorously".
Jacobs died in London in 1997. His book, The Adventures of Willy the Wizard - No 1 Livid Land, was published in 1987, according to the estate representatives, based in Australia.
Bloomsbury said Jacobs's estate first approached it in 2004 but was "unable to identify any text in the Harry Potter books which was said to copy Willy the Wizard".
"JK Rowling had never heard of Adrian Jacobs nor seen, read, or heard of his book Willy the Wizard until this claim was first made in 2004," the statement read.
The Harry Potter series has sold more than 400 million books worldwide in 65 languages and spawned a series of hit films starring Daniel Radcliffe as the boy wizard.