Why it matters: A US Appeals Court gave the green light to a class-action lawsuit over Facebook's photo-tagging suggestions. The beleaguered social media platform is accused of collecting and storing facial biometric data and violating BIPA. The court denied a motion to breakup the class action. If found guilty, Facebook could face billions of dollars in penalties.

A federal appeals court ruled that a class-action lawsuit against Facebook over its facial recognition technology could proceed as planned. The 9th Circuit Court of Appeals in San Francisco denied the social media's motion to have the class action broken up into individual lawsuits.

The case was filed in 2015 and claims that Facebook collected the biometric data of users without their consent. Facebook argued that each plaintiffs' claim would be unique, so they should be required to file as individuals.

The court disagreed unanimously ruling 3-0 "that the development of a face template using facial-recognition technology without consent (as alleged in this case) invades an individual's private affairs and concrete interests."

"The facial-recognition technology at issue here can obtain information that is 'detailed, encyclopedic, and effortlessly compiled,' which would be almost impossible without such technology," wrote Judge Sandra Ikuta.

"We have always disclosed our use of face recognition technology and that people can turn it on or off at any time."

Collecting such information without consent violates the California Biometric Information Privacy Act (BIPA). It is alleged that a Facebook photo feature uses stored facial information to make tagging suggestions to users of friends that may appear in their uploaded photos.

Penalties for BIPA violations range from $1,000 for each negligent breach to $5,000 for reckless or willful acts. Reuters notes, plaintiff attorney Shawn Williams indicated that the affected class might include as many as seven million users. If found guilty Facebook could face billions of dollars in damages.

Facebook contends that it has done nothing wrong.

"We have always disclosed our use of face recognition technology and that people can turn it on or off at any time," said a spokesperson for the company.

Facebook's assurances rang hollow, however, thanks to its numerous and recent run-ins with user privacy issues. Despite that tagging suggestions seem to be a perfectly harmless application of the technology, organizations like the ACLU applauded the ruling.

"The capability to instantaneously identify and track people based on their faces raises chilling potential for privacy violations at an unprecedented scale," said ACLU attorney Nathan Freed Wessler in a statement. "Both corporations and the government are now on notice that this technology poses unique risks to people's privacy and safety."