In securities class actions that allege violations of Section 11 of the Securities Act of 1933, "officers and directors are liable together with the corporation for material misrepresentations in the registration statement." To have "standing" to sue under Section 11 of the 1933 Act in a class action, a plaintiff must be able to prove that he can "trace" his shares to the registration statement and offering in question, as to which there is alleged a material misstatement or omission. In the absence of an ability to actually trace his shares, such as when securities issued at multiple times are held by the Depository Trust Company in a fungible bulk and physical tracing of particular shares may be impossible, the plaintiff may be barred from pursuing his claim for lack of standing.