OLEAN — European authorities have approved the Siemens AG’s purchase of Dresser-Rand.

The approval, which followed an in-depth investigation started in February by the European Commission (EC),  was announced early Monday. The deal is expected to close today.  

Dresser-Rand officials announced the purchase in September following months of rumors and speculation. In an all cash deal, Siemens, a Germany-based energy conglomerate, is buying Dresser-Rand for $7.6 billion and assuming all of the company’s debts. The purchase represents Siemens’ foray into the domestic oil and gas industry.

“After a detailed assessment of the markets involved, the commission is satisfied that European consumers will not be negatively affected by the merger,” said  Margrethe Vestager, commissioner of the EC. “Today’s decision proves that even after an in-depth analysis, the commission can unconditionally approve a merger if it does not have a negative effect on competition.”

Monday’s news comes several months after Dresser-Rand announced it was reducing its workforce by 8 percent, or 650 workers. The layoffs, company officials said, were in response to lower oil prices and not the impending merger.

Almost a year ago, international media outlets began reporting on rumors of the impending sale.

Most notably, Manager Magazin, a trade publication based in Germany, reported in early July 2014 Siemens’ purchase of Dresser-Rand had been in the works for months.

The magazine also reported Siemens Chief Executive Joe Kaeser had mandated an offer for Dresser-Rand, which had a market value of $4.6 billion at Wednesday’s closing price, and would consider a hostile takeover if necessary.  

Rumors of the potential acquisition caused Dresser-Rand’s stock to surge up 19 percent at one point Thursday, with shares trading for more than $70. Siemen’s stock, however, went down.

About two months after the sale was publically announced, Dresser-Rand shareholders voted with a 99 percent majority in November in favor of the sale.

Dresser-Rand has 13 manufacturing facilities in eight countries and maintains a network of 49 service and support centers covering more than 150 countries. The company employs 7,200 workers.

Dresser-Rand is one of the largest employers in the region. Its operations in Olean, Wellsville and Painted Post have a combined workforce of 2,220 — with around half working in Olean.