In a telephone interview, Mr. Winkelman, who co-owns Tecolote Books with Mr. Simon, said that the company would retain its current editorial leadership, with Elaine Szewczyk as editor and Eric Liebetrau as managing editor. Mr. Winkelman said that Mr. Simon was "an inveterate and unquenchable and voracious reader" who was a longtime subscriber to Kirkus, which was founded in 1933. "The idea that Kirkus was leaving was a real shame for him," Mr. Winkelman said.

In a statement, Mr. Simon said: "With the growth of e-books and e-reading devices, no one can really see the future of publishing. But turmoil like this creates opportunities. At a time when even the definition of a book is changing, my love of books makes me want to be part of the solution for the book publishing industry."