In December 2006, Exxon Mobil Corp. convened a two-day summit of environmental and ethics experts at a rural retreat near the base of the Blue Ridge Mountains in Virginia. It was nearly a year after Rex Tillerson took over as chief executive, and a month after Democrats had claimed a new majority in Congress. The world’s largest publicly traded oil company found itself in a bind.

For decades, Exxon had funded far-right think tanks that seeded doubt over the scientific consensus on climate change. Under Tillerson’s predecessor, Lee Raymond, the company had aligned itself heavily with Republicans, funneling 95 percent of its political donations to the party from 2000 to 2004, according to Steve Coll’s 2012 book, Private Empire: ExxonMobil and American Power. Raymond took an aggressive stance against climate science: “It is highly unlikely that the temperature in the middle of the next century will be affected whether policies are enacted now or 20 years from now,” he said in a 1997 speech.

Tillerson and Ken Cohen, Exxon’s PR chief and chair of its political action committee, wanted to broaden the company’s political reach. One step was changing their messaging about climate change, moving away from the denial the company had been attacked for supporting. The Blue Ridge retreat was part of that effort, and brought together more than a dozen guests, which according to Coll’s account, included “two senior energy-policy analysts from the Brookings Institution, a human rights activist at Freedom House, climate specialists, business ethics professors, socially responsible investors, and religious activists.”

As Coll wrote, “Tillerson’s own views about climate science were not greatly different from Lee Raymond’s,” though Tillerson “did not claim or wish to project the same sort of independent scientific expertise that Raymond had offered about climate science.” But Tillerson did see that the company needed to reposition itself.

“All they were saying they were going to do is simply acknowledge that it might exist, as opposed to saying it does not exist,” Jennifer Bremer, an economic development consultant who attended the meeting as a guest, told The Huffington Post. Bremer said Exxon executives had called the retreat so the attendees could give them some advice, not so they could dictate the company’s new policy.

“You don’t just bring in a couple of hippies and start discussing internal deliberations,” Bremer added. “Not if you’re Exxon.”

ROBYN BECK via Getty Images President-elect Donald Trump nominated Rex Tillerson to serve as secretary of state.

Not long after the summit, Exxon began to modify its public stance on climate change. Its 2007 Corporate Citizenship report announced that the company would “discontinue contributions to several public policy groups whose position on climate change could divert attention from the important discussion on how the world will secure energy required for economic growth in an environmentally responsible manner.”

The company announced its first big investment in biofuels two years later, vowing to spend $600 million on research into algae-based transportation fuels. In 2015, the firm backed the historic climate agreement reached in Paris, a stance it reiterated four days before this year’s election.

Tillerson, who President-elect Donald Trump has now nominated as his secretary of state, has gotten a lot of credit for Exxon’s shift away from climate denial. But even as Exxon learned to talk the talk, the $378 billion company has failed to walk the walk.

Tillerson “brought a more clever approach, a more PR-savvy approach, to climate at Exxon, but the company really didn’t change its stripes much,” said Kert Davies, who leads the Climate Investigations Center and was the creator of ExxonSecrets, a Greenpeace program tracking the company’s climate denial. “They managed to drop this campaign of using surrogates, scale that back enough that it took the pressure off.”

In June 2009, the House passed a bill to set up a cap-and-trade system limiting carbon emissions. But that legislation failed to gain traction in the Senate. Exxon undertook an aggressive lobbying campaign that year, spending $27.4 million ― more than the entire environmental lobby combined, according to the nonpartisan Center for Responsive Politics. The American Petroleum Institute ― of which Exxon Mobil is a member ― launched its own PR campaign against the legislation.

Meanwhile, Tillerson put Exxon’s new public positioning into action, making headlines when he said publicly he preferred a tax on carbon ― a policy that was not under debate in Congress at the time, but was also politically implausible at best, considering it was in the middle of the Great Recession.

Some environmental leaders said the discussion about a carbon tax at that point was “ “a distraction” from the urgent need to put a cap on carbon emissions. “[W]e can’t wait for lawmakers, industry, and the American people to spend years hashing out the details of an entirely new system,” wrote Frances Beinecke, then-president of the Natural Resources Defense Council.

RIA Novosti / Reuters Tillerson has been widely criticized by leaders in both parties for his close ties to Russian President Vladimir Putin.

Tillerson continued the company’s repositioning on the science as well, testifying before Congress in 2010 that “there is no question the climate is changing, that one of the contributors to climate change are greenhouse gases that are a result of industrial activities.” Six months after his testimony, the Senate climate bill died.

Supporting a carbon tax wasn’t necessarily a cynical ploy to undermine the cap-and-trade bill; there are practical reasons a company like Exxon would support of a carbon tax. A handful of fossil-fuel companies already assign a price to carbon emissions for their internal accounting, including Exxon. As more countries take steps to cut carbon emissions as part of the Paris agreement, Exxon has said it prefers a predictable tax on carbon to a cap-and-trade system that is open to market fluctuations.

But even as recently as last year, Exxon continued to fund organizations that deny or downplay climate science, and proposed solutions to global warming. In 2015, the company spent nearly $2 million on more than a dozen such think tanks and advocacy groups, according to data compiled by Greenpeace and vetted by the Union of Concerned Scientists. That list ranges from the U.S. Chamber of Commerce, the country’s largest industry association, to more radical groups, such as The Federalist Society for Law and Public Policy Studies, which has called global warming “nothing more than an educated guess,” and the Mountain States Legal Fund, which once described itself as the “litigation arm” of an “anti-environmental” movement.

And unlike many of its industry rivals, Exxon has failed to invest seriously in renewable energy. The company ranked below all of its U.S. and European competitors on reducing emissions and issuing corporate guidance on the risk posed by climate change, according to a November report from the British shareholder advocacy group CDP.

Tillerson has openly mocked the clean-energy industry for years, joking once that he wasn’t “really against renewables” because wind turbine operators bought Exxon’s oil as a lubricant. “The more windmills are built, the more oil we sell,” he said. At a May 2015 shareholders meeting, Tillerson said he hadn’t invested in renewables because “we choose not to lose money.”

Even the company’s touted biofuel efforts have been slow to yield anything concrete. By 2013, Exxon tweaked its approach, refocusing its efforts to produce gasoline from genetically modified algae after spending one-sixth of the $600 million it had pledged to spend on biofuels. In September 2015, the firm kicked off a new partnership with Michigan State University to research algae-based fuels, but devoted just $1 million to the project. In January, Exxon signed a deal with a clean-energy developer to start researching new ways of distilling ethanol. Yet, even for a company whose yearly earnings were roughly halved to $16.2 billion last year by low oil prices, the investments seem like an afterthought. Exxon spent $8.8 million on political lobbying this year.

Saying climate change is real doesn't absolve you from continuing to fund climate denial. Jamie Henn, a spokesman for the environmental group 350.org

Nor has Exxon ever fully owned up to the years it spent undermining climate science. That came into full view in October, when InsideClimate News and the Los Angeles Times published reports revealing that the company understood global warming decades ago and covered it up anyway ― long before Tillerson’s supposed shift. The reports uncovered evidence that Exxon’s in-house scientific experts understood the role that burning fossil fuels played in global warming in the 1980s, yet instead of acting on that science, the company funded a Big Tobacco-style disinformation campaign.

“Exxon Mobil does not fund climate denial,” Alan T. Jeffers, a spokesman for Exxon, told HuffPost by email, insisting the company views the risk of climate change as real. “We provide funding to a broad range of groups but they don’t speak for us and we don’t necessarily agree with all their positions on any given issue.”

Neither Tillerson nor the Trump administration’s transition team replied to emailed requests for comment.

The Exxon exposé led a coalition of state attorneys general to begin working together to investigate corporations for allegedly misleading the public about climate change. Exxon has aggressively defended itself against the probe, calling it “biased attempts to further a political agenda for financial gain.”

“Tillerson is using half-truths to cover up decades of lies,” Jamie Henn, a spokesman for the environmental group 350.org, told HuffPost. “Saying climate change is real doesn’t absolve you from continuing to fund climate denial. It shouldn’t surprise anyone that the world’s largest oil company is good at greenwashing ― they spend more money on it than they do on renewable energy development.”

Kate Sheppard contributed reporting.