Jk Rowling wasn't kidding around when she vented her frustration over being outed as the writer of The Cuckoo's Calling last year. The book was written under a pseudonym, and it turns out it was a lawyer who revealed the Harry Potter author as the true writer.

JK RowlingJK Rowling arrives in London in 2011

According to the BBC, lawyer Chris Gossage was the leak in the case. He reportedly told his wife's best friend about Rowling's connection, and has since been fined by the Solicitors Regulation Authority.

Gossage faced much bigger problems though. Rowling also took legal action against Gossage and a friend for revealing the information via Twitter to a journalist, but later accepted an apology and charity donation.

The £1,000 fine (or a little more than $1,600) from the SRA was for breaching privacy rules, "by disclosing confidential information about a client to a third party."

The SRA continued, by saying that Gossage should "act in the best interests of each client" and "behave in a way that maintains the trust the public places in you and in the provision of legal services".

Rowling was upset that that the company had breached her privacy in such a way.

"I feel very angry that my trust turned out to be misplaced," she said back in July. "To say that I am disappointed is an understatement."

JK RowlingJK Rowling at the premiere of 'Harry Potter and the Deathly Hallows'

The Cuckoo's Calling, by Rowling's pen name Robert Galbraith, has climbed in popularity since the true author was revealed.

"To those who have asked for a sequel, Robert fully intends to keep writing the series," Rowling said, "although he will probably continue to turn down personal appearances."