The Federal Trade Commission has been hit by a “tidal wave” of merger cases and cannot review all of them before the required deadlines.

The FTC is now sending letters to merging entities warning them that the agency may consider a combination illegal even if the companies decide to merge.

“Companies that choose to carry out transactions that have not been thoroughly investigated do so at their own risk,” the regulator said in a statement on Tuesday.

The alert can give hospitals merging at a steady pace a break. Unraveling agreements once they have already been concluded can be costly and complex. Pre-merger filings give regulators the ability to stop anti-competitive mergers before a deal is reached, thus avoiding harming consumers and businesses in the meantime.

The FTC received 343 pre-merger requests in July, more than three times the amount of July of last year, when 112 transactions were submitted for review.

So far this year, more than 2,000 transactions have been submitted during the month of July, according to FTC figures, eclipsing the 815 filings during the same period last year.

Federal regulators have already forced hospitals to unwind the mergers.

The FTC forced ProMedica to unwind its takeover of St. Luke’s Hospital in the Toledo area after alleging the deal would severely hamper competition. The FTC then approved a divestiture plan in 2016 after a long court battle.

The latest FTC alert comes as agreements with hospitals are expected to be subject to further scrutiny under a recent executive order from President Joe Biden.

It came even as the FTC signaled its intention to prioritize enforcement in a number of key industries, including healthcare.

Additionally, last year the FTC said it was expanding a key tool in its arsenal to potentially help monitor future transactions.

Mergers that exceed a certain threshold – currently $ 92 million – are required to submit a pre-merger case to the FTC under the Hart-Scott-Rodino Act.

The filing opens a review period during which the FTC and the Department of Justice investigate the agreement.

Typically, agencies have 30 days to determine if additional information is needed. If so, the deal is put on hold until the companies respond with the necessary information, and after that, the agencies have a limited number of days to file a dispute if they find the reconciliation illegal.

The FTC can also end the waiting period earlier, which allows the transaction to continue.

However, the agency reserves the right to challenge any agreement, whether or not it has been reviewed.