23 to provide explicitly for private aiding and abetting liability actions under Section 10(b) would be contrary to [the] goal of reducing meritless securities litigation.” S. Rep. No. 104-98, at 19 (1995). There is no hint that the same claims could proceed simply by relabelling them as claims for primary conduct. To the contrary, in the PSLRA, Congress sought to avoid the kinds of chilling effects caused by litigation risk that “scheme” liability claims in private class actions would create. See H.R. Rep. No. 104-50, at 20 (1995) (“Fear of litigation keeps companies out of the capital markets.”); see also 143 Cong. Rec. S10475, S10477 (daily ed. Oct. 7, 1997) (“if our markets are to remain ahead of those in London, Frankfurt, Tokyo, or Hong Kong, we must create uniformity and certainty”); supra, at 6-8. More generally, Congress is presumed to know the law when it legislates. Merrill Lynch, Pierce, Fenner & Smith, Inc. v. Curran, 456 U.S. 353, 379 (1982). Thus, Congress knows that “[a]s a general rule, the principle of stare decisis directs [this Court] to adhere not only to the holdings of [its] prior cases, but also their explications of the governing rules of law.” County of Allegheny v. ACLU, 492 U.S. 573, 668 (1989) (Kennedy, J., concurring); see also Carey v. Musladin, 127 S. Ct. 649, 655 (2006) (Stevens, J., concurring) (stare decisis includes “explanatory language” for the Court’s ruling even if “such guidance . . . may not have been strictly necessary as an explanation of the Court’s specific holding”). Central Bank explicated why aiding-and-abetting was inconsistent with the necessary elements for primary liability. First, Central Bank held: “As in earlier cases considering conduct prohibited by § 10(b), we again conclude that the statute prohibits only the making of a material misstatement (or omission) or the commission of a manipulative act.” 511 U.S. at 177 (emphasis added). Commercial counterparties do not make statements to the market about the issuer or have the duty to disclose necessary for liability for a material omission.
