(Bloomberg) — Kimmeridge Energy Management Co., an outspoken shale investor, criticized Devon Energy Corp.’s divestment program as too slow after the driller’s $25 billion takeover of Coterra Energy Inc.

It’s the latest sign of frustration from an activist investor that urged Devon in a May letter titled ‘Time for Action’ to shed assets outside of the Permian Basin, the most productive US oil field. Kimmeridge voted against all of Devon’s directors and the compensation plan at its annual meeting, according to a person familiar with the information who asked not to be identified. 

“When we published our ‘time for action’ letter in May, we expected the board to respond with the urgency warranted by Devon’s persistent underperformance,” Mark Viviano, managing director at Kimmeridge, said in a statement Thursday. “Unfortunately, the board’s response to date has fallen well short of the urgency the situation demands. This is not what we envisioned when we voted in favor of the transaction.”

Devon received an $8 billion offer from Stone Ridge Asset Management for its Marcellus Shale natural gas assets, Reuters reported in late May, citing four anonymous sources.

Another activist, Toms Capital Investment Management shares the view that Devon should be moving to shed assets and has become increasingly impatient with the pace of management’s actions at Devon, according to a separate person familiar with the matter. Toms, which is a top five shareholder in the stock, is considering all options to spur action at Devon, the person added. 

A Devon spokesperson didn’t immediately respond to a request for comment for this article. Little more than two weeks ago, Devon Chief Executive Officer Clay Gaspar told investors in New York that the company is moving with haste to evaluate its portfolio, calling it a months-long rather than a years-long exercise.

Outside of the Permian, Devon has oil and gas assets in the Rocky Mountains, the Anadarko Basin of Oklahoma, the Eagle Ford in South Texas and the Marcellus in Pennsylvania.

(Updates with details of second activist starting in fifth paragraph)