Ocean Properties Ltd., a New Hampshire-based development and hospitality company, has sold partial interest in 18 of its hotels in a joint venture with a private investment firm in New York.

The Portland Marriott at Sable Oaks is the only Maine hotel affected by the deal, and all 18 hotels will continue to be managed and operated by Ocean Properties. No personnel changes will take place, according to Richard Ade, Ocean Properties’ chief financial officer, who confirmed the July 2 merger on Friday.

“We see this as a real opportunity for us to expand even further throughout the United States,” Ade said.

Founded by Bangor native Thomas Walsh, Ocean Properties is a private, family-owned company based in Portsmouth, N.H. Ocean Properties employs about 10,000 people and owns and manages about 120 hotels in North America, including five hotels in Bar Harbor, the Samoset Resort in Rockport, and the Fairfield Inn in Bangor.

Ade declined to reveal what Lockwood Capital paid in the deal, but he said the merger will give Ocean Properties access to large cash assets held by investment firms in New York.

On Wednesday, the Portland City Council’s community development committee recommended Ocean Properties be picked for the $100 million redevelopment of the Maine State Pier, which the city owns.

“We’re constantly looking for development opportunities,” Ade said.