Candy maker Mars Inc. says it’s buying confectioner Wm. Wrigley Jr. Co. in an all-cash deal valued at almost $23 billion.

Under the agreement announced Monday, shareholders at Chicago-based Wrigley would receive $80 in cash for each share of common stock and Class B common stock. After the buyout is completed in six to 12 months, Wrigley would become a subsidiary of McLean, Va.-based Mars, maker of M&Ms, Snickers bars and other candy.

Billionaire Warren Buffett’s Berkshire Hathaway Inc. is making a minority equity investment in the new Wrigley subsidiary.

Wrigley produces such gums as Extra, Eclipse, and Orbit.