Chesapeake Energy Corp said on Wednesday its internal probe of the financial dealings of outgoing Chief Executive Aubrey McClendon found no intentional wrongdoing.

A series of Reuters investigations last year triggered civil and criminal probes into the second-largest U.S. producer of natural gas. Big shareholders took control of the board in June after McClendon was stripped of the chairmanship of the company he co-founded in 1989.

Last month, Chesapeake said McClendon was stepping down as CEO. McClendon cited philosophical differences with the board as the reason for his departure.

The Oklahoma City, Oklahoma, oil and natural gas company also said on Wednesday that its board had concluded that no antitrust laws were violated in connection with the acquisition of Michigan oil and gas rights in 2010.

Last June, Reuters reported that Chesapeake had plotted with Encana Corp, its top competitor, to suppress land prices in the Collingwood shale formation in northern Michigan. The matter is the subject of investigations by both the state of Michigan and the U.S. Department of Justice.

A Reuters investigation last April found McClendon had arranged to personally borrow more than $1 billion from EIG Global Energy Partners, a firm that is a big investor in Chesapeake.

The loans, arranged through McClendon's personal shell companies, were secured by his interest in Chesapeake wells. Under a controversial program called the Founders Well Participation Program (FWPP), McClendon is allowed to take up to a 2.5 percent stake in every well Chesapeake drills.

Chesapeake said last month the probe by its board of directors had at that point found no improper conduct.