I’m afraid the new Supreme Court case on antitrust conspiracies, Twombly, is quite insignificant, notwithstanding the view of the estimable Baseball Crank that it “will almost certainly be the most practically significant case of this term.” All the case holds is that bare allegations of a conspiracy and parallel conduct do not suffice without more specificity. That much was the widespread actual practice in the lower courts even before this decision. What we really needed guidance on was which “plus factors” would, coupled with parallel conduct, suffice to make out an antitrust conspiracy. On that the opinion is of no help. So all it really does is slap down one wayward decision without really settling anything important for the future.