Bloomsbury Publishing Plc on Monday denied allegations that author J.K. Rowling copied "substantial parts" of a book by another children's author when she wrote "Harry Potter and the Goblet of Fire."
The book, published in 2000, was the fourth installment of the hugely successful boy wizard Harry Potter series that has sold more than 400 million copies worldwide and been turned into a multi-billion-dollar film franchise.
"The allegations of plagiarism made today, Monday 15 June 2009, by the Estate of Adrian Jacobs are unfounded, unsubstantiated and untrue," said a statement from Bloomsbury, which publishes Harry Potter in Britain.
"This claim is without merit and will be defended vigorously."
In an earlier statement, Jacobs' estate said that it had issued proceedings at London's High Court against Bloomsbury Publishing Plc for copyright infringement.
"The Estate is also seeking a court order against J.K. Rowling herself for pre-action disclosure in order to determine whether to join her as a defendant to the ... action," the statement read.
It named the estate's trustee as Paul Allen, and said that Rowling had copied "substantial parts" of "The Adventures of Willy the Wizard -- No 1 Livid Land" written by Jacobs in 1987.
It added that the plot of Harry Potter and the Goblet of Fire copied elements of the plot of Willy the Wizard, including a wizard contest, and that the Potter series borrowed the idea of wizards traveling on trains.
"Both Willy and Harry are required to work out the exact nature of the main task of the contest which they both achieve in a bathroom assisted by clues from helpers, in order to discover how to rescue human hostages imprisoned by a community of half-human, half-animal fantasy creatures," the estate statement said.
"It is alleged that all of these are concepts first created by Adrian Jacobs in Willy the Wizard, some 10 years before J.K. Rowling first published any of the Harry Potter novels and 13 years before Goblet of Fire was published."
According to the statement, Jacobs had sought the services of literary agent Christopher Little who later became Rowling's agent. Jacobs died "penniless" in a London hospice in 1997, it said.
In its response, Bloomsbury said 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, almost seven years after the publication of the first book in the highly publicized Harry Potter series.
"Willy the Wizard is a very insubstantial booklet running to 36 pages which had very limited distribution. The central character of Willy the Wizard is not a young wizard and the book does not revolve around a wizard school."
Bloomsbury added that the claim was first made in 2004 by solicitors acting on behalf of Jacobs' son, who was the representative of his father's estate.
"The claim was unable to identify any text in the Harry Potter books which was said to copy Willy the Wizard."