Apple Inc. (AAPL)  has filed a sweeping antitrust lawsuit against patent lawsuit machines Acacia Research Corp. (ACTG) , and Conversant Intellectual Property Management Inc., accusing them of colluding with Nokia Corp. “to extract and extort exorbitant revenues” from Apple and other cellphone makers.

Apple accuses Acacia and the other companies of evading their obligation to license patents that have been incorporated into cellphone industry standards on fair and reasonable terms.

…

Mark Lemley, director of Stanford Law School’s law, science and technology program, said Apple was wise to take a stab at arguing an illegal conspiracy by the plaintiffs rather than a monopolization claim as has been tried in other antitrust suits against patent assertion entities. “The suits have usually not been successful, in part because it is hard to prove monopolization by an entity that doesn’t itself make products,” he said. “The strongest theory, if true, would be some sort of collusion between Nokia and Acacia about who is targeted.”