There have been absolutely wild scenes recounted in court today as Sydney-based designer Katie Jane Taylor – nee Katie Perry – has taken on international singer Katy Perry over a name trademark issue dating back to 2009, ABC News reports.

The court heard that Katy Perry allegedly called Taylor a “dumb bitch” in a savage-ass email chain discussing the trademark application.

“This dumb bitch won’t stop,” the singer allegedly wrote in a 2009 email. Swish swish, bish, indeed.

Perry’s manager Steven Jensen allegedly responded to the email chain, claiming the issue had been “blown way out of proportion.”

After learning of the application in 2009, the singer’s lawyers reportedly sent the designer a cease and desist letter, prompting Taylor to go public with the case.

Jensen defended his client in court, saying it wasn’t directed at Taylor personally. He tried to lessen the blow of Perry’s scathing words with the ol’ tortured, emotional artist defence. Classic.

“Katy Perry is an artist,” Jensen said. “Artists are emotional people. Emotions are what drive their talent. That was an emotional response, not directed at Ms Taylor personally.”

Mr Jensen added that the singer was upset that Taylor appeared to be “seeking publicity” through the trademark case.

Katy Perry’s camp sent the designer a letter in June 2009 informing her that her use of the trademark was “misleading or deceptive.”

It warned of the possibility of filing an injunction and said Taylor could be liable for damages and legal fees “likely to run into the vicinity of $50,000”.

Jensen told the court that the letter was not intended as a threat.

“I consider it a normal business approach,” he said.

There were subsequent discussions about putting out a joint statement to clarify the situation, but Katy Perry asked her people to “keep me out of it entirely.”

“Don’t soften it up, don’t apologise, nothing,” were her instructions, the court heard.

Both parties were unable to reach a mutual agreement, hence why the case has now gone to trial.

The trial is expected to run until Friday, so buckle up, binches.