The plaintiffs said Avid Dating Life Inc., which owns and operates the website, failed to safeguard their personal and financial information, marketed a “full delete removal” service that did not purge user account information from its database, and populated its accounts with fake female users to lure male customers.

The ruling, by Judge John A. Ross of the United States District Court in the Eastern District of Missouri, noted that plaintiffs in cases involving accusations of rape, child sexual abuse and other sensitive matters have been allowed to use pseudonyms. Other court cases, though, have found that mere embarrassment was insufficient to outweigh the presumption of openness and public scrutiny in judicial proceedings.

“Moreover, the personal and financial information plaintiffs seek to protect has already been released on the Internet and made available to the public,” he wrote in the ruling, which was dated April 6 and was brought to light earlier this week in Ars Technica.

Avid argued that the sexual preferences and habits of the plaintiffs “do not constitute information of the utmost intimacy” that would require withholding their names, the judge wrote.

The judge ruled that those who want to proceed as class representatives, who have a fiduciary obligation to represent the entire class of plaintiffs and who “generally receive an incentive award as compensation for work done on behalf of the class,” must disclose their identities.

They could dismiss their complaints and proceed, without publicly disclosing their names, as class members if and when a class is certified. Class members will not need to be identified by name, the judge ruled.