Shares of the online genealogy site Ancestry.com Inc. plunged in trading Monday after NBC announced that it would not renew family history show "Who Do You Think You Are?" for a fourth season.
The show tracks celebrities as they find their family history using Ancestry's services. The company is also a sponsor of the show.
Ancestry.com CEO Tim Sullivan said the series had "inspired many viewers to follow their passion to learn more about who they are and where they come from."
He said the company has a great partnership with the show's producers, Is or Isn't Entertainment and Shed Media, and looks forward to exploring other distribution options.
Ancestry.com, based in Provo, Utah, has 1.9 million paying subscribers. Citi Investment Research analyst Mark Mahaney said the NBC show, which premiered in the U.S. in March 2010, had helped the company add subscribers.
The company's stock made major gains in the show's early days, peaking at $45.79 in April 2011. Its shares fell $3.47, more than 13 percent, to $22.69 in late afternoon trading Monday.