What is the statute of limitations in securities fraud cases?

These cases involve federal securities fraud claims under section 10(b) of the 1934 Act, 15 U.S.C. 78j(b), and S.E.C. Rule 10b-5. Because the private 10b-5 suit is a judicially created "implied right of action," section 10(b) and Rule 10b-5 contain no statute of limitations provision. At the time the Appellants here filed their complaints, the law of this circuit applied to these cases a statute of limitations period derived or "borrowed" from state law. See Reeves v. Teuscher, 881 F.2d 1495, 1500 (9th Cir.1989).