Challenges to U.S. mergers and acquisitions are up.

According to yesterday’s joint annual report from the Federal Trade Commission (FTC) and the Department of Justice’s (DOJ) Antitrust Division, the agencies challenged 44 deals during the 2012 fiscal year. The amount is a 19 percent jump from challenges during the 2011 fiscal year.

Steven Salop, a law professor at Georgetown University, told Thomson Reuters that the increase in challenges demonstrates the Obama administration’s greater emphasis on antitrust enforcement and litigation. “That’s been part of their rhetoric, and they haven’t been afraid to go to court,” he said.

Although most of the challenges resulted in settlements, the agencies completely blocked some deals, such as 3M Co.’s proposed $550 million acquisition of Avery Dennison Corp.

The Hart-Scott-Rodino Act of 1976 requires businesses to report proposed M&A deals to the government. In sum, businesses reported 1,429 proposed transactions during the 2012 fiscal year, which is about the same amount submitted in the 2011 fiscal year.

For more InsideCounsel news and insight about M&As, read:

Cheat Sheet: What GCs need to know about government merger enforcement trends

How antitrust authorities view mergers and acquisitions

“E-Merging”: Mergers and acquisitions in today’s era of big data

A records management checklist for mergers and acquisitions

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