Oklahoma City–based SandRidge Energy has hired Mayer Brown to conduct an independent investigation into a series of questionable land deals by CEO Tom Ward and his family that helped spark a revolt among the oil and gas company’s shareholders.

The launch of the Mayer Brown–led inquiry, which was announced Monday, comes a month after SandRidge ended a proxy battle with activist hedge fund TPG-Axon Capital Management. At the heart of that fight was a push by TPG-Axon—which owns a 7.3 percent stake in SandRidge—and other activist investors to dump Ward amid mounting questions about his outsize compensation, the transactions now being scrutinized, and the company’s declining share price.

As The Am Law Daily reported last month, SandRidge in settling the proxy fight agreed to either fire Ward or to cede control of its board to a group of TPG-Axon-backed directors. The settlement also called for an outside law firm to conduct an independent review of the land deals involving Ward and his family. SandRidge, which must make a decision on Ward’s fate by June 30, expects Mayer Brown to finish its investigation by June 15.

A Mayer Brown spokeswoman said the firm had no comment on any aspect of its work for SandRidge.

TPG-Axon CEO Dinakar Singh has accused Ward of profiting from "self-dealing" in a series of transactions in which companies owned by the CEO and his family have bought land and then sold it to SandRidge at a mark-up. In a November letter to the SandRidge board, Singh called it "astonishing" that Ward had made roughly $150 million as SandRidge’s CEO over the previous five years, according to Bloomberg. SandRidge’s board also paid Ward $67 million in 2008 in exchange for ending a company program that gave him the right to personally invest in wells being drilled by the company.

(Ward is the former president of Chesapeake Energy, the oil and gas company he cofounded with Aubrey McClendon, who officially retired as that company’s CEO earlier this month after running afoul of shareholders for using Chesapeake funds to finance personal loans. Ward and McClendon are both part owners of the National Basketball Association’s Oklahoma City Thunder franchise.)

SandRidge also announced Monday that it has appointed David Lawler, who previously served as an executive vice president at the company, as its chief operating officer. SandRidge also said its board is "evaluating a variety of options for addressing the company’s future capital needs and lessening any funding shortfall, including potential asset monetizations." The company has already sold off corporate aircraft and reduced spending on advertising and sponsorships in order to raise capital.

In December, Covington & Burling—which often advises SandRidge on transactional matters and acted as the company’s outside counsel on the settlement with TPG-Axon—represented SandRidge in connection with its sale of oil assets in Texas’s Permian Basin to Sheridan Production Partners for $2.6 billion. (In resolving the proxy fight, TPG-Axon was advised by a Schulte Roth & Zabel team.)

Former Vinson & Elkins attorney Philip Warman serves as SandRidge’s general counsel.