Equitable estoppel is an argument which posits that (for example) the statute of limitations should  not bar an action, because defendant led plaintiff on, and kept plaintiff from timely filing a case.  In WASHINGTON MUTUAL BANK, Plaintiff, -against- LESTER YOUNG, RAYMOND MAR, MARILYN HARRIS, AKA MARILYN SELLER, US BANK NATIONAL ASSOCIATION, et al,  the argument succeeds for plaintiff.

"The statute of Limitations applicable to actions alleging conversion is three years (CPLR 214 [3]; Herman v Depinies, 273 AD2d 146, 710 N.Y.S.2d 899 [1st Dept 2000]), which begins to run at the time of the alleged theft even if the plaintiff is then unaware of it (Herman v Depinies, 273 AD2d 146, 710 N.Y.S.2d 899, supra.). Since the Check was deposited into the Beneficial account on March 11, 2005, Harris had until March 11, 2008 to bring her conversion claim. Thus, her conversion claim, commenced on July 7, 2008, more than three years after the alleged taking of the property occurred, is untimely (Close-Barzin v. Christie’s, Inc.., 51 A.D.3d 444, 857 N.Y.S.2d 545 [1st Dept 2008]).

However, as argued by Harris, equitable estoppel may be invoked to defeat a statute of limitations defense where the "’plaintiff was induced by fraud, misrepresentations or deception to refrain from filing a timely action’" (Kaufman v Cohen, 307 AD2d 113, 122, 760 N.Y.S.2d 157 [1st Dept 2003] quoting [*8] Simcuski v Saeli, 44 NY2d 442, 448-449, 377 N.E.2d 713, 406 N.Y.S.2d 259 [1978]). The doctrine of equitable estoppel "requires proof that the defendant made [**7] an actual misrepresentation or, if a fiduciary, concealed facts which he was required to disclose, that the plaintiff relied on the misrepresentation and that the reliance caused plaintiff to delay bringing timely action" (Kaufman v Cohen, 307 AD2d at 122; see also Powers Mercantile Corp. v Feinberg, 109 AD2d 117, 490 N.Y.S.2d 190 [1st Dept 1985], affd 67 NY2d 981, 494 N.E.2d 106, 502 N.Y.S.2d 1001 [1986]). Here, Harris alleges that Dalley willfully concealed his involvement as a partner of Beneficial and a signatory of the checks that dispersed the underlying funds from Beneficial’s account, which prevented the discovery of such information in a timely manner. The record relied on by Dalley to oppose Harris’s equitable estoppel argument raises issues of fact, inter alia, as to whether Harris was aware of Dalley’s relationship with Beneficial, prior to the expiration of the statute of limitations, and therefore whether the doctrine of equitable estoppel should be applied in the within circumstances. In particular, Dalley alleges that three (3) months after the closing date, Harris received a Beneficial check dated May 5, 2005, signed by Dalley, raising a factual issue as to whether Harris was aware of Dalley’s connection to Beneficial, [**8] prior to the expiration of the statute of limitations. Thus, that branch of Dalley’s motion to dismiss the fraud and conversions claims on the grounds of the statute of limitations is denied."