Private equity firm Kimmeridge Energy Management Co. LLC on Tuesday continued with its quest to sap more value from onshore explorer PDC Energy Inc. by filing preliminary proxy materials with the Securities and Exchange Commission that include its picks for the board of directors.

The energy-focused firm named three candidates early last month and notified PDC of its intent to nominate them at the annual meeting, which has not yet been scheduled. Kimmerdige began pushing the company earlier this year to improve its performance after it acquired more than 5% of the stock.

Kimmeridge, which has panned PDC’s operational and financial performance, initially wanted its concerns addressed during the company’s fourth quarter earnings call and included in the plans for this year. Absent action, the private equity firm warned that it would explore a variety of strategic alternatives such as assets sales or even the company.

PDC has said little other than it values all shareholder concerns and that its board already includes highly qualified members. The company said in March it would review the nominees and make recommendations in its definitive proxy materials.

Kimmeridge said Tuesday it is seeking to “elect a slate of director candidates for the purpose of changing a minority of the board to include a set of experienced industry professionals who think and act like shareholders.” Managing Partner Ben Dell, who founded Kimmeridge in 2012, said over the coming weeks the firm plans to have discussions with PDC shareholders about strengthening the independent operator.

Kimmeridge’s board nominees include Dell, along with Alice Gould, a director at CorePoint Lodging Inc., and James Adelson, who serves as CEO of Nadel and Gussman LLC, an Oklahoma-based oil and gas producer.

PDC works primarily in the Permian Basin of West Texas and the Denver-Julesburg Basin of northeast Colorado. The company’s year/year production increased 26% to 110,000 boe/d in 2018, when net income declined to $2 million from $127.5 million in 2017. The bulk of the company’s operations are located in Colorado, which accounted for 84,000 boe/d of production last year.

PDC entered the Permian in 2016 after buying assets managed by Kimmeridge, which has pushed for consolidation among smaller operators in the play.