Hitachi, Ltd. (TSE:6501) is planning to sell its 40% stake in an air-conditioning joint venture with Johnson Controls International plc (NYSE:JCI), according to people familiar with the matter. Such a move would likely mean an outright sale of Johnson Controls-Hitachi Air Conditioning (Hitachi-Johnson Controls Air Conditioning, Inc.). Johnson, which owns the other 60%, has for months been exploring a sale of its heating and ventilation assets, including the joint venture.

A deal could value the joint venture at almost JPY 500 billion ($3.2 billion), the people said, asking not to be identified discussing confidential information. Considerations are at an early stage, they said. A representative for Hitachi said no decision has been made at this point, and that the company is considering ways to ?enhance its corporate value.?

Hitachi has first right of refusal on Johnson?s stake in the joint venture, Bloomberg News has reported previously.