LONDON (Reuters) - Gay dating app Grindr ( GRND ) is facing a mass data protection lawsuit in London from hundreds of users who allegedly had their private information, including HIV status, shared with third parties without consent, a law firm said on Monday.

Austen Hays, which said the lawsuit is being filed at London's High Court, said thousands of Grindr ( GRND ) users in the United Kingdom may have been affected.

The firm alleges users' highly sensitive information, including HIV status and the date of their latest HIV test, were provided to third parties for commercial purposes.

Grindr ( GRND ) said in a statement provided to the Guardian that it planned to "respond vigorously to this claim, which appears to be based on a mischaracterisation of practices from more than four years ago".

Austen Hays said around 670 people had signed up to the lawsuit over breaches said to have taken place between 2018 and 2020, with potentially thousands more joining the case.

Austen Hays' Managing Director Chaya Hanoomanjee said in a statement: "Grindr ( GRND ) owes it to the LGBTQ+ community it serves to compensate those whose data has been compromised and have suffered distress as a result, and to ensure all its users are safe while using the app, wherever they are, without fear that their data might be shared with third parties."

Grindr ( GRND ) did not immediately respond to a request for comment. The Guardian reported a Grindr ( GRND ) spokesperson as stating: "We are committed to protecting our users data and complying with all applicable data privacy regulations, including in the UK.

"We are proud of our global privacy program and take privacy extremely seriously." (This story has been corrected to fix the spelling of Hays from Hayes, in paragraphs 2 and 5)