Gasthalter & Co. is working with Engine No. 1 LLC, as the newly formed investment firm has launched a proxy fight at ExxonMobil to pressure it to “implement a strategic plan for sustainable value creation.”

Once the country’s most valuable company, stock of the Irving, TX-based company has crashed with the plummeting demand for fossil fuels and its lack of investment in the alternate energy sector.

The Dow Jones Industrial Average embarrassed ExxonMobil in August when it eliminated its stock from the index after a 100-year run and replaced it with Salesforce.

In its Dec. 7 note to ExxonMobil CEO Darren Woods, the investment firm says that company shareholders suffered a 20 percent drop in total returns over the past decade as the S&P 500 posted a 277 percent gain.

“It is clear, however, that the industry and the world it operates in are changing and that ExxonMobil must change as well,” said Engine No. 1.

Engine No. 1 wants to refresh Exxon’s 10-member board via the election of four independent directors.

The San Francisco-based says that if ExxonMobil wants to avoid the fate of other once-iconic American companies, it must better position itself for long-term, sustainable value creation."

Gasthalter & Co.’s Jonathan Gasthalter and Amanda Klein represent Engine No. 1.