Charles and David Koch are no longer contemplating a purchase of the Tribune Company’s chain of newspapers, a spokeswoman for the billionaire industrialists said on Thursday.

The spokeswoman, Melissa Cohlmia, affirmed a report by the conservative news Web site The Daily Caller that said Koch Industries — where Charles is chairman and chief executive and David is an executive vice president — had concluded that the acquisition was “not economically viable.”

But other acquisitions in the media industry might be: “Koch continues to have an interest in the media business, and we’re exploring a broad range of opportunities where we think we can add value,” Ms. Cohlmia said in a statement. She declined to elaborate. …

The ensuing controversy drew unwanted attention to the Kochs, who had previously shown just a passing interest in media investments.