To win approval for the deal, which was valued at $13.4 billion when it was announced in November, the companies agreed to sell assets used to produce bulk oxygen, bulk nitrogen, bulk argon and other products in certain markets.
The companies said in a joint statement that the FTC approval was the final regulatory hurdle. They said they plan to close the deal on May 23.
The companies agreed to divest 16 facilities used to make bulk oxygen, nitrogen, and argon, two used to make nitrous oxide, four that make liquid carbon dioxide and dry ice, two that make just liquid carbon dioxide and three welding gas stores, the FTC said in a statement.
Analysts had said that buying Airgas - the leader in U.S. packaged gases - will help Air Liquide to overtake rivals Linde, Air Products and Praxair to take the top spot in North America and speed diversification away from slow-growth Europe.
Reporting by Diane Bartz; Editing by W Simon and Dan Grebler
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