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

Tribune declined to comment on the news reports about the Kochs on Thursday, but a spokesman said the company’s plan to spin off the newspapers was proceeding apace. That plan was announced in July as an alternative to selling the newspapers right away, though a sale of all or some of the papers could still happen.

In the spinoff, Tribune-owned Web sites like CareerBuilder.com will be separated from the print publications, potentially removing an important stream of advertising revenue for the papers. The Daily Caller’s report quoted an anonymous source as saying that the newspaper acquisition would not be palatable for the Kochs without that Web revenue.

Ms. Cohlmia said that “In terms of the Tribune, the Daily Caller story is accurate.”

The Daily Caller’s source also said Koch Industries’ interest in the newspapers faded “a couple months” ago. In July, when Charles Koch was interviewed by The Wichita Eagle, the local newspaper where Koch Industries is based in Kansas, he said a bid for Tribune’s newspapers was possible — “it’s not on the front burner, but it’s possible.”

“There are tremendous changes going on in media, in taking media as a whole, all forms of communication. We’re back at square one analyzing where is the most change, where are the best opportunities for new entrants to come in and add value. And so newspapers are one, but there are all sorts of others. There’s the Internet, there’s TV. There’s entertainment. And so we don’t know where we’ll end up on that,” Mr. Koch told the paper.