Southern District of Texas Certifies Investor Class in Anadarko Securities Case

On March 10, 2026, the United States District Court for the Southern District of Texas again certified a nationwide class of investors in a securities fraud class action against Anadarko Petroleum Corporation. The district court previously certified the class in 2022, but the Fifth Circuit vacated that order and remanded for further proceedings. On remand, Robbins Geller Rudman & Dowd LLP successfully re-briefed and argued class certification, resulting in the court’s renewed certification order.

This ruling is critical because class certification is often the decisive battleground in securities fraud litigation. Without it, most investors lack a viable path to recovery. By certifying the class, the court ensured that thousands of injured investors can pursue their claims collectively, promoting efficiency, consistency, and accountability under the federal securities laws.

The action arises from allegations that Anadarko and certain of its senior executives misled investors regarding the viability of the company’s Shenandoah deepwater oil project in the Gulf of Mexico. Plaintiffs allege that defendants made materially false and misleading statements that overstated the project’s prospects while concealing adverse operational results and risks that artificially inflated the company’s common stock price in violation of §10(b) of the Securities Exchange Act of 1934 and Rule 10b-5.

In May 2017, Anadarko announced that it was suspending appraisal activity on the Shenandoah project and recorded write-offs totaling over $900 million tied to the project, including impairment and exploratory costs, allegedly causing investors to suffer losses when the company’s common stock price dropped.  Following this corrective disclosure, the market absorbed the truth about Shenandoah’s failure, and Anadarko’s stock price declined, causing substantial investor losses.

In the opinion certifying the class, the court concluded that “both the record evidence and common sense point to the same conclusion. And that is, when news broke on the same day of both an actual $900 million write-off as to the [Shenandoah project] and a potential $140 million in new regulatory costs as to an entirely different event, an eight percent decline in the company’s stock price the following day isn’t solely attributable to the latter regulatory costs.”

The case now proceeds on behalf of all similarly situated investors, positioning the class to seek full recovery for losses caused by defendants’ misconduct and to hold Anadarko and its executives accountable.

Robbins Geller attorneys Mark Solomon, Daniel S. Drosman, Luke O. Brooks, Hillary B. Stakem, and Nicole Q. Gilliland represent the plaintiffs.

In re Anadarko Petroleum Corporation Securities Litigation, 2026 WL 673470 (S.D. Tex. Mar. 10, 2026).