The NBA champion Boston Celtics are on the market.

Wyc Grousbeck, the Celtics’ majority owner and governor, announced Monday he is putting the team up for sale just weeks after the franchise won its 18th NBA title.

The 63-year-old Grousbeck, a Worcester native and lifelong Celtics fan, led an investment group that bought the Celtics for $360 million in 2002. He oversaw the team’s two most recent championship runs — the first in 2008 led by Paul Pierce, Kevin Garnett and Ray Allen, and this year’s Jayson Tatum- and Jaylen Brown-led squad.

Speaking with reporters after the Celtics’ most recent championship parade two weeks ago, Grousbeck offered no indication that he was planning to sell the team.

“It feels like we’ve got more to do,” he said. “I mean, I’ve got to go design a ring with the guys, and we’ve got to raise the banner in October. There’s more to do. But we’re going to build the team for next year. We’re going to enjoy this for now, though.”

He later added: “We’re fans who bought this team. We’re all in this together. Let’s go get another one.”

This is a developing story and will be updated.