The bill came out of a campaign promise made by President François Hollande to the 629 employees of the ArcelorMittal blast furnaces in Florange, which shut down permanently a year ago amid a bitter row between the government, unions and ArcelorMittal boss, Lakshmi Mittal.
It was initially to have been passed at the end of last year, which could have forestalled the plant’s closure but it is only now coming up for debate in parliament and will go to a vote on 1 October.
The bill has watered down Hollande's promise to force bosses to sell businesses if they were making a profit, proposing only that companies with more than 1,000 employees would be forced to try and find a buyer or pay the equivalent of two years unemployment benefit for every job lost.
And, although the ruling Socialists are joined by their allies, the Greens, and the small Left Radical party in supporting the proposal, it’s under fire from both the left and the right.
The right-wing opposition UMP has called the bill an "economic Waterloo" that will scare off investors.
The 20 Communist Party MPs say they will abstain from voting, saying the bill does not go far enough to protect jobs.
The government has agreed to invest 300 million euros in Lorraine, the former industrial region where the Florange furnace was situated.
Hollande is set to return to the site during October.