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Facebook users have until Monday to claim their share of a $650 million class action settlement over alleged violations of the state's biometric privacy law.

Nearly 1.4 million people had filed a claim as of Wednesday, which would make the expected payout about $400 each, Chicago attorney Jay Edelson said.

In April 2015, Edelson filed the initial lawsuit in Cook County Circuit Court on behalf of plaintiff Carlo Licata, alleging the social media giant's use of facial tagging features without consent was not allowed under Illinois privacy law.

The case was moved to Chicago and then California federal court, where it attained class action status.

In January, Facebook agreed to settle the lawsuit for $550 million, but U.S. District Judge James Donato denied the initial request for approval. After subsequent negotiations, Facebook agreed to increase the settlement to $650 million, and the court approved it in August.

The settlement class includes Facebook users in Illinois for whom the social network created and stored a face template after June 7, 2011, according to court records. To qualify, Facebook users had to live in the state for at least six months over the last nine years—before the final Aug. 19 court-approved settlement.

Illinois Facebook users can file a claim through Monday at a website created for the biometric privacy .

The state's Biometric Information Privacy Act is among the strictest such laws in the U.S., and has spawned a number of lawsuits. It requires companies to get permission before using technologies such as facial recognition to identify customers.

In August, a Chicago woman filed a lawsuit alleging Macy's violated Illinois' biometric privacy law by using video surveillance cameras and technology on its customers. The lawsuit, which is also seeking class action status, is ongoing in Chicago federal court.

Edelson said the Facebook settlement sends a clear message to companies about the increased use of biometric technologies without permission.

"This is a total game-changer when it comes to , biometric rights," Edelson said. "Biometric privacy, along with geolocation , is the big battleground over the next five years."

As part of the settlement, Facebook agreed to set its face recognition default setting to off, and to delete all existing and stored face templates for class members unless it obtains express consent from the user.