First saw it mentioned in Shelf Awareness Pro, here's an article about it. And here's an interesting bit:

He also shrugged off antitrust concerns over owning two such big companies. Simon & Schuster is the third biggest publisher in the US, although it has a smaller global reach than PRH. Rabe said: “We looked at this and we don’t think it is an issue. If you look at the market holistically, particularly the strength of Amazon, and it includes self-publishing and the like, we don’t think this will be an obstacle.”