I find it odd that the commentators on this graphic haven't pointed out the magic date late in the 1990s when the United States ceased to have its own legal publishing industry, all of the three majors having fallen to foreign ownership.
I might quibble about the inclusion of Brad Hildebrandt and David Baker's businesses when acquired by Thomson. And what does Elite have to do with legal publishing. They are all businesses providing technology products and services or management consulting services that happen to be owned by a legal publisher.
But it's still a great graphic [click on it to enlarge it]: