GRAND RAPIDS, Mich. (WOOD) — Leaders at Cedar Fair, L.P., the company that owns Michigan’s Adventure, Cedar Point and several other amusement parks, has confirmed it has received a proposal to sell to SeaWorld.

In a statement posted to its website, Cedar Fair called the proposal “unsolicited” and “non-binding.”

Cedar Fair’s stock price jumped more than 15% following the announcement. SeaWorld’s share price also rose slightly.

Michigan’s Adventure first opened in Muskegon County in 1956 as Deer Park, including a petting zoo and a children’s play area. The owners added more attractions and rides through the years and rebranded to Michigan’s Adventure in 1988. According to MLive, ownership sold the park to Cedar Fair in 2001 for $28 million.

This is not the first sales proposal for Cedar Fair. Six Flags offered to buy out the company in 2019 for $4 billion, but Cedar Fair officials turned it down.