Private equity firm KSL Capital Partners has acquired the parent company of the Pig Hotels in partnership with its co-founder Robin Hutson.
It is understood KSL has taken a significant share, buying out shareholders including Jim Ratcliffe.
Hutson retains a stake and will continue to run the business as chairman while Tom Ross, previously group operations director, has taken on the role of managing director.
The investment will allow the Pig, which was founded in 2011 and runs eight boutique hotels in southern England, to further expand throughout the UK.
Huston said the deal was an "exciting opportunity for the Pig to focus on the future".
He added: "KSL invests in some of the most iconic and well-known hotels in the world and has had great success preserving what makes each asset unique. The investment will allow us to continue to grow and expand our collection, while offering our guests the same home away from home quality they expect at each of our hotels."
KSL is an experienced hospitality investor and previously owned the Hotel du Vin group, which was founded by Hutson in 1994, as well as Malmaison before it sold the pair to Frasers Hospitality for £363m in 2015.
Tina Yu, principal at KSL, said: "Having been admirers of what Robin has built over the last decade, we could not be more excited to work hand-in-hand with him and the entire team, and to help continue the growth of the Pig.
"The team at The Pig has created something truly unique and exceptional: hotels set in the English countryside which are dedicated to providing genuine hospitality and are at the forefront of environmental responsibility. We look forward to being part of this journey and supporting the management team."
Terms of the deal were not disclosed