"We had always found Chevron's involvement in the NTNG project a little confusing given the major had no direct path to the Gladstone export projects and another Greenfield LNG project on the east coast of Australia is unlikely," the bank said after Chevron made its move on Monday.

In terms of the positive news for Beach, which is searching for a new NTNG partner, JPM said Chevron had carried a large amount of the "science experiment to date" including 18 wells with 16 that were fracced.

"Beach has been provided a free look at the asset for the past two years however the company has not progressed that far up the learning curve as production pilot testing had yet to be commenced," JPM said.

A key part of JPM's underweight recommendation on Beach, which includes a price target of 86c per Beach share when they traded at $1.08 each, was due to how it gave no valuation credit for unconventional gas out of the Cooper.

"We do not incorporate any value for Beach's Cooper shale potential as we believe it has a number of obstacles to reaching a competitive position in the cost curve, including high carbon dioxide content and lack of liquids," the bank said.

"Within the Cooper Basin players, due to relative valuation and asset mix, we prefer both Drillsearch and Senex over Beach."

Macquarie Wealth Management downgraded its rating of Beach to neutral following Chevron's exit.

"Following Chevron's withdrawal Beach appears catalyst-light over coming months," Macquarie said in a research note," Macquarie said.

"Furthermore, with the new managing director only recently commencing, communication of the new strategy is likely to be also a number of months away."