Private equity firms are known for squeezing every last dime out of a portfolio company, but it turns out there may be tactics to further increase profits.

According to SRS|Acquiom, which helps manage post-closing activities in private mergers and acquisitions, outdated processes such as shareholder verification cost buyers and sellers in the private market an estimated $5 billion a year in the U.S. or $500,000 per deal.

A common problem, it said is leaving money in escrow idle, which typically earns almost nothing in interest.

“Paying an actual interest rate on an escrow? I haven’t done escrow for a while that pays anything,” said Drew Backstrand, general counsel at lower midmarket firm North Central Equity.

Buyers in a private equity deal typically leave 7% to 10% of the deals’ price tag in a money market bank account for roughly 18 months, as a protection against any mishap with the transaction.

Capital preservation and the flexibility demanded of the sum, together with historically low interest rates, means the money in escrow often earns one to three basis points, or one to three hundredth of a percent, in interest.

SRS|Acquiom said its data found that the escrow money often spends the whole 18 months in the bank account. By managing the escrow for multiple companies of various private equity investors, it said it can help bargain with individual banks for an additional 15 to 20 basis points in interest rate. Assuming an additional yield of 15 basis points, SRS|Acquiom said the industry can earn $340 million a year.

“It can go to help pay transaction-related expenses like legal fees,” said Paul Koenig, a co-chief executive of SRS|Acquiom. “It is meaningful.”

Private equity firms have been creative in the companies they back and the structure with which deals are struck, but antiquated practices remain when it comes to closing a transaction. For one, physical stock certificates are still very much in existence in the private market and are often mailed back and forth as proof of one’s ownership of a company.

SRS|Acquiom said the hassle related to the paper process, including errors in data input, costs the industry $100 million a year, and will slow down the receipt of final payment by weeks, which it estimates result in another $4.9 billion in lost economics.