Gov. Gavin Newsom was poised Wednesday to sign new worker-classification rules that threaten to upend the gig economy, raising fresh criticism from the top lawyer at Uber Technologies and setting the stage for a likely wave of new lawsuits across industries.

After hours of debate Tuesday night and Wednesday morning, state lawmakers sent Newsom Assembly Bill 5, a measure that will codify a landmark California Supreme Court ruling last year. That decision made it more difficult for gig companies not to classify their workers as employees entitled to wider protections such as minimum wage and benefits. Newsom has said he will sign the bill.