New York CNN Business  — 

A proposed $30 billion insurance industry merger is off, one month after the Justice Department’s antitrust regulators sued to block it. It’s another sign of the tough stance the Biden administration is taking against corporate deal-making.

The deal between Aon (AON), which is incorporated in England and Wales, and Ireland-based Willis Towers Watson (WLTW), was announced in March 2020. Both have major operations in the United States and around the rest of the globe and thus needed the approval of US antitrust regulators.

The deal, valued at $30 billion at that time of its announcement, would have combined two of the insurance industry’s largest brokers.

Although European antitrust regulators and some other regulators approved the deals, the US Justice Department sued in June to block the deal. Attorney General Merrick Garland said last month the Justice Department was committed to preserving competition and stopping harmful consolidation.

The two companies issued a joint statement that said they are convinced their businesses were different enough to not cause any harm from reduced competition, but that it did not make sense to move forward with the deal in the face of the Justice Department opposition.

“The DOJ position overlooks that our complementary businesses operate across broad, competitive areas of the economy,” said Aon CEO Greg Case. “We are confident that the combination would have accelerated our shared ability to innovate on behalf of clients, but the inability to secure an expedited resolution of the litigation brought us to this point.”

The two companies aren’t well known to most Americans, despite their size.

Aon has $11 billion in annual revenue and 50,000 employees globally. Willis Towers Watson has $9 billion in revenue and 46,000 employees, and is probably best known by the general public for having its name on the Chicago skyscraper (formerly known as Sears Tower) that was once the world’s tallest building, even though it sold the building to Blackstone Group (BX) in 2015.

Still, the fact that the Biden administration is taking a much more aggressive stance when it comes to antitrust cases is a significant change from the policy of previous administrations, both Democrat and Republican.

And this is not the first major deal killed due to opposition from the Biden administration. Earlier this month Warren Buffett’s Berkshire Hathaway (BRKA) pulled the plug on a deal to buy a big natural gas pipeline for more than $1.7 billion because of antitrust concerns.

The Federal Trade Commission has changed some of its rules recently that could make it easier to go after tech companies like Amazon (AMZN) that may offer attractive prices to customers, but have also been accused of harming small businesses, workers and innovation. It previously operated under rules that would prioritize “consumer welfare” in its enforcement decisions.

President Joe Biden also signed an executive order earlier this month with 72 specific actions designed to increase competition and reduce market concentration from deals that were approved in years past, such as looking into the allocation of airport gates to promote competition in an airline industry in which four carriers formed by mergers now control more than 80% of US air travel.

“Competition keeps the economy moving and keeps it growing. Fair competition is why capitalism has been the world’s greatest force for prosperity and growth,” Biden said at the ceremony at which he signed the executive order. “But what we’ve seen over the past few decades is less competition and more concentration that holds our economy back. We see it in big agriculture, in big tech, in big pharma. The list goes on. Rather than competing for consumers, they are consuming their competitors.”