Award-winning composting firm Ecological Sciences has been bought by environmental service provider Glendale.
Based at Exeter University, Ecological Sciences processes 40,000 tonnes of green waste from the West Country annually.
Founded in 1995, the firm won the Composting Association's Jim Balance Compost Marketing award in 2004.
Glendale managing director Nick Temple-Heald said the purchase would lead to a "strong presence in the marketplace as local authorities come under increasing pressure to meet strict recycling targets".
Ecological Sciences general manager Steve Bullock added: "Our acquisition by Glendale is a tremendous opportunity, and will allow our expertise to reach local authorities on a national level."