New details are emerging on United Technologies decision to sell or “spin-off” their almost 100-year-old helicopter business Sikorsky Aircraft.

Defense News is reporting that UTC is currently reviewing bid offers from several of the world’s largest aerospace companies. While offers from Lockheed Martin, Textron, and Airbus made it past the initial bid stage for the sale of United Technologies’ subsidiary Sikorsky Aircraft, there are still significant obstacles to overcome.

The acquisition by either Airbus or Textron, both of which already manufacture helicopters, could raise antitrust concerns of an overly large share of the helicopter production market. Additionally, as a foreign company, Airbus would also receive extra scrutiny from regulators, in both Europe and the US.

That acquisition would drop the number of American Helicopter manufacturers from two to three. An acquisition by another helicopter company could hamper Sikorsky’s tradition of creating quality aircrafts. “I think you’re going to have a real tough time letting Sikorsky go to a big helicopter maker already,” an industry analyst stated in the article, “At some point you have to have some competition or there’s no reason to innovate anymore.”

Lockheed may be the best fit with its already successful business, integrating mission systems and sensors for helicopters, but it may yet decide not to start actually manufacturing them. With Sikorsky’s strong financials, a spinoff is still on the cards as it would significantly reduce United Technologies tax liability compared to a sale.