(Reuters) - Companies are racing against the clock this week to notify antitrust agencies about pending deals before a new, more stringent merger filing rule passed during President Joe Biden's administration comes into effect, lawyers said this week.

The U.S. Federal Trade Commission rule taking effect after 5 p.m. on Friday is estimated to triple the average workload to gain regulatory clearance, which is required for transactions worth more than $126.4 million.

The rule is meant to bring merger clearance requirements up to date, account for the increase in U.S. private equity deals, and give regulators more information so they can clear deals more quickly, according to the FTC.

Companies with pending deals are scrambling to submit so they can avoid paying increased compliance costs of $40,000 or more, attorneys said. They are also trying to take advantage of having more than 40 years of guidance and practice on the old rule, instead of becoming the first to test the new ones.

"There is going to be a mad rush to get filings in this week," said Aleksandr Livshits, an antitrust partner at law firm Fried Frank.

The new merger filing rule will expand the amount of information collected under the Hart-Scott-Rodino Act, which sets out regulatory requirements for mergers. It was unanimously approved by the Federal Trade Commission in October. Chairman Andrew Ferguson, who succeeded Lina Khan in January, called the rule "a lawful improvement over the status quo" when it passed.

None of the attorneys Reuters spoke to viewed the rush as an attempt to avoid scrutiny, but some expressed concern that the bump in filings coming amid President Donald Trump's push to shrink the federal workforce could result in problematic deals not receiving adequate review.

Merger filings in December 2024 and January 2025 were already higher than average, and the third highest year-over-year for the past decade, according to FTC data. The FTC has not released data for the first week of February, though antitrust attorneys at seven law firms confirmed they are seeing more deals than usual filed this week.

The American Economic Liberties Project, an antimonopoly group, said the influx should raise alarms.

"The Trump administration's antitrust enforcers should rigorously scrutinize these under-the-radar deals to ensure fair competition for honest American businesses, workers, and consumers," said AELP communications manager Jimmy Wyderko.

A spokesperson for the FTC declined to comment on Thursday.

Even as they seek to meet the deadline, lawyers are watching closely to see if the new rule will be paused.

"I hold out hope that it won't go into effect next Monday, but the time for a suspension is vanishing quickly," said Lisl Dunlop, an antitrust partner at Axinn, Veltrop & Harkrider.

The private equity industry has criticized the new rule, which requires disclosure of relationships with competitors.

The American Investment Council, a private equity industry group, sued along with the U.S. Chamber of Commerce to block the rule. But no ruling is expected this week.

Members of Congress are considering legislative action to review the rule, said sources who requested anonymity to speak.

"What would be ideal for dealmakers, is if Congress does act, that the FTC takes notice and decides that for continuity purposes, they would keep the current rules in place," said Livshits.

An immediate suspension of the rule would require a vote from the FTC, which is currently divided between Democrats and Republicans.