For years, advertising executives have largely escaped criticism for glossing the images of major polluters.

But as climate protestors turn up at ad agency offices and dozens of U.S. states file lawsuits accusing oil companies of deliberately spreading disinformation, the industry is coming under increasing scrutiny. U.N. Secretary-General António Guterres has called ad execs working with the fossil fuel industry “Mad Men fuelling the madness.”

Now, a new DeSmog report reveals which advertising companies have helped oil giants ExxonMobil, Chevron, BP, and Shell spend a collective $1.5 billion on buying U.S. ad space since the Paris Agreement to tackle climate change in 2015.

Below we’ve ranked their CEOs — the real life “Mad Men” — according to the estimated amount of oil company ad spend serviced by their company on their watch. (Click on the portraits to read a profile of their firm).

Note: Two of these companies — IPG and Omnicom — merged in November but have been considered separately as they were individual entities throughout the analysis period.

Mark Read, who stepped down last year amid nosediving profits, was one of the more outspoken ad industry leaders on climate change, despite WPP consistently having the most fossil fuel clients of any advertising company in the world under his leadership. In 2022, Read argued against a burgeoning industry movement to divest from fossil fuel clients, telling an audience of financial analysts: “We are there to support them on [their energy] transition.” Since then, an ad made by WPP agency VML has been banned by the UK advertising regulator for misrepresenting Shell’s business as greener than it actually is; a U.S. Congressional committee report cited a series of ExxonMobil ads made by WPP agency Group SJR as examples of greenwashing; and campaigners lodged a complaint (yet to be ruled upon) with the OECD alleging WPP had broken guidelines on climate and human rights. At the time, a WPP spokesperson said, “Contrary to the claims being made, we adhere to the highest regulatory standards in our work for clients.”

The longest serving CEO in this list, John Wren has overseen Omnicom’s lucrative longstanding relationship with ExxonMobil — which has a long history of funding climate science denial. Most notably, a group of Omnicom ad agencies developed ExxonMobil’s long-running algae-fuel ads. Hundreds of millions of dollars were spent on advertising a “climate solution” that few experts believed would ever leave the lab. Omnicom’s acquisition of IPG in November means Wren’s combined oil and gas client list is now the longest of any advertising CEO in the world. Although Omnicom has made some promises to reduce its operational emissions, the firm has never made any public move under Wren to restrict the nature of its work for the fossil fuel industry.

An accountant by trade, Michael I. Roth’s 15 years at IPG saw the company sign with ExxonMobil in 2011. Since then, a group of IPG media-buying agencies have managed hundreds of millions of dollars’ worth of ad space for the oil giant to help it reach its desired target audiences. Roth’s reign also saw IPG become the go-to advertising partner for Saudi Aramco, the world’s biggest oil company — although those ad dollars are not included in this analysis. Roth left IPG in 2020, having earned nearly $200 million across 15 years, according to executive intelligence firm Equilar. When inducting him into the American Advertising Federation Hall of Fame, the federation described him as “a champion-level voice for what is good and right.”

Arguably the most famous (and richest) man in the ad industry. WPP’s founder Sir Martin Sorrell turned wire basket maker Wire & Plastic Products into the biggest advertising company in the world — and until recently the biggest provider of communications services to the fossil fuel industry. Sorrell was knighted in 2000 for his contributions to the business world. By 2015, his annual salary was over $90 million. He eventually left WPP in a cloud of controversy over allegations of personal and financial misconduct. A Financial Times investigation at the time said anonymous interviews with WPP staff painted “a picture of routine verbal abuse of underlings and a blending of Sir Martin’s corporate and private life”. Sorrell denied all the allegations against him.  

“I strongly believe that a brand that [does] not invest into this [clean energy] transition will be out of business in 10 years,” declared Yannick Bolloré in August 2023. The following month, Havas won a multimillion-dollar contract to handle Shell’s global ad placement strategy. Shell had U-turned on its renewable energy targets in favour of maintaining oil and gas production just months earlier. Insiders told DeSmog at the time that employees were taken aback, having watched Bolloré cultivate a personal brand of caring about the climate (though the deal was less surprising if you knew the Bolloré family’s business empire is partly built on transporting oil). Facing Extinction Rebellion die-ins at the Havas offices and the loss of a climate-focused client, the youngest “Mad Man” on this list has dug in, repeating in various interviews that “the most effective change comes from within.” In the end, four Havas agencies ended up losing their B-Corp certifications for ethical businesses over the Shell deal, and Havas had to warn investors the reputational damage could impact its financial performance.

Dentsu’s CEOs have tended not to make personal statements in the media on advertising’s relationship with the fossil fuel industry. Nevertheless, under Hiroshi Igarashi’s leadership, Dentsu took a significant step when it decided to quietly publish its “advertised emissions” in an investor risk report — representing the amount of carbon pollution associated with the uplift in sales resulting from its advertising campaigns, such as an airline ad leading to greater demand for flights. Dentsu found these were 32 times higher than the emissions from its core operations, such as powering its offices. Igarashi has shown no sign of moving Dentsu on from its lucrative contracts with Chevron and Shell — two of 18 fossil fuel clients Dentsu currently serves, according to research by industry campaign group Clean Creatives.

Toshihiro Yamamoto started his career with Dentsu back in 1981. A full 26 years later, the Dentsu veteran replaced the outgoing Tadashi Ishii as CEO, tasked with steadying the ship after Ishii left in a cloud of controversy. Yamamoto’s five years in charge saw the Japanese ad giant add Shell to its client roster, when its business-to-business ad agency Merkle gained control of a share of the hundreds of millions the oil giant spends on advertising each year. By the time Yamamoto departed in 2021, Dentsu had upped its fossil fuel contracts from five when he started his tenure to at least 11, according to DeSmog research.

In September 2022, Philippe Krakowsky announced an “industry first” climate policy that would restrict its work with fossil fuel companies. The new policy didn’t apply to existing clients. In an internal memo at the time, Krakowsky — like Read and Bolloré — told staff, “it is important to be in the room” with clients such as ExxonMobil to “positively impact their business transformation journeys.” Since Krakowsky sent this email, ExxonMobil has said it plans to increase production by more than a million barrels a day by 2030 and build four new gas projects. In August, a DeSmog investigation published with the Financial Times revealed allegations from staff that IPG was in breach of Krakowsky’s climate policy, after leaked documents showed it was helping Saudi Aramco — the world’s biggest oil company — target government policymakers. IPG and Krakowsky did not respond to the allegations. Krakowsky became the Chief Operating Officer at Omnicom in November after IPG was bought by its New York rival, a deal which earned Krakowsky a $48.6 million payout.

Under Tadashi Ishii, Dentsu led Chevron’s advertising strategy in the U.S., making ads that painted the oil giant as a steward of the environment and promoted speculative climate solutions like carbon capture. One ad from 2012 said “protecting people and the environment is a core value” at Chevron. In 2013, Ishii oversaw the $3.2 billion purchase of UK ad agency Aegis.  The Aegis acquisition saw Dentsu inherit major fossil fuel contracts not included in the analysis, such as French oil giant TotalEnergies.

Note: Big Oil ad spend figures for each CEO only cover the years they were in charge from the 2015 Paris Agreement onwards, even if they were in the job prior to this.

Art by Sabrina Bedford. Design by Sari Williams.