Belfor Holdings Inc., the Birmingham-based property restoration giant, has sold for an undisclosed amount to a New York City-based private equity firm that has been active in metro Detroit in recent years.

The deal was approved by the European Commission — Belfor has offices in more than 20 countries — in March and is acknowledged on the American Securities LLC website, which says the investment took place in April. Belfor has not publicly announced the sale.

American Securities declined comment on Monday morning. Emails sent to Belfor on Friday afternoon and Monday morning went unanswered.

Belfor reported $1.96 billion in revenue last year to Crain's, up 9 percent from $1.79 billion in 2017. (Moody's says about 40 percent of Belfor's revenue comes from outside the U.S.) Belfor said it had 2,190 local employees as of January.

The American Securities website says Belfor has 8,400 total employees and that four American Securities executives are on the Belfor board: Loren Easton, managing director of American Securities; managing director and CEO Michael Fisch; David Musicant, managing director; and Aaron Maeng, principal. Easton is serving as chairman.

Sheldon Yellen remains listed as the company's CEO, along with his brother Michael Yellen as COO. Theresa Williams is executive vice president of national sales and marketing and Rusty Amarante is director of operations.

A February Moody's rating changed Belfor's from positive to negative based on a $310 million increase in debt as a result of American Securities' leveraged buyout. A press release from S&P announcing its downgrade of Belfor says that the deal is being funded in part with a $200 million revolving credit facility due in 2024 and a $585 million term loan due in 2026.

The downgrade was because of the volatile nature of the restoration business. Ratings agencies noted that natural disasters are highly profitable for Belfor but unpredictable, and insurance companies don't typically reimburse restoration companies until the fourth quarter. That produces a lot of short-term borrowing for operations. In addition, the company gets roughly 40 percent of its revenue from outside the U.S., producing "exposure to foreign exchange headwinds," Moody's says.

Belfor came to Michigan from Denver in 2001 after acquiring Masco Corp.'s Inrecon LLC, reportedly one of the largest property restoration businesses in the world at that time, and moving Belfor USA's headquarters here.

Belfor traces its company roots to the founding of Quality Awning & Construction in 1946, which in 1980 was turned into Inrecon (short for "insurance reconstruction").

A 2017 Forbes profile of Yellen says that Belfor has worked on more than 1 million sites. The magazine at the time estimated the company to be worth $900 million, with Yellen himself worth $320 million.

The profile says Yellen had been discussing a private equity sale even then.

"Yellen says he was days away from cashing out his own stake in the business a couple of years ago, after agreeing to sell Belfor to a private equity firm in what he claims was a billion-dollar deal. At the last minute he backed out, claiming he couldn't bear to abandon his employees," Forbes wrote.

In March, Gallatin, Tenn.-based property restoration franchisor Servpro Industries Inc. and New York City-based private equity firm Blackstone Group (NYSE: BX) announced a deal that gave the latter a majority ownership stake in the former. Terms of the deal weren't revealed, but The Wall Street Journal said it was more than $1 billion including debt. Servpro had 1,700 franchises, but revenue figures weren't known.

American Securities has long been active in metro Detroit's automotive sector, most recently, selling Southfield-based Metaldyne Performance Group to American Axle & Manufacturing Holdings in a $3.3 billion deal.

It had acquired Metaldyne for $820 million in 2012, Royal Oak-based group HHI Group also in 2012 for an undisclosed price and Southfield-based Grede Holdings in 2014 for more than $800 million to form Metaldyne Performance Group.

Also in 2014, American Securities acquired Novi-based day-care firm Learning Care Group Inc. for an undisclosed amount.