Katy Perry, the singer, has lost a trademark fight with Katie Perry, an Australian fashion designer.

Katie Taylor, who sells garments as Katie Perry, sued the pop star, claiming that her merchandise infringed on a trademark she held.

A judge ruled on Friday that clothes marketed for Katy’s 2014 Australian tour did infringe on Katie’s trademark.

“This is a tale of two women, two teenage dreams, and one name,” noted Justice Brigitte Markovic in her decision.

The judge ruled that the Teenage Dream singer, born Katheryn Hudson, used the Katy Perry moniker in “good faith” and does not owe the designer any personal compensation.

Kitty Purry, the star’s firm, must pay damages, which will be assessed next month.

The story of ‘David and Goliath’