WPP's Fossil-Fuel Ad Spend Exposes Climate Policy Gap

What the DeSmog report found

The DeSmog report, published on 30 April 2026, estimates that agencies within the WPP (LSE: WPP) network placed approximately $1.5bn (£1.1bn) in US advertising on behalf of ExxonMobil, Chevron, Shell and BP over the decade following the 2015 Paris climate agreement, as first reported by the Guardian.

That figure is roughly double the estimated amounts linked to each of WPP's two nearest US-based rivals, Omnicom and Interpublic Group (IPG), according to DeSmog's methodology. Omnicom and IPG completed their merger in November 2025, creating the world's largest advertising holding company by revenue and consolidating spend that had previously been split across two separate groups.

DeSmog's analysis drew on publicly available media-buying data to attribute estimated spend to parent holding companies via their subsidiary agencies. The platform acknowledged limitations in tracking exact dollar flows through complex agency networks but argued the scale of the disparity was significant enough to warrant scrutiny, according to the report.

WPP has not publicly disputed the specific dollar figure. The Guardian report noted that the company was approached for comment prior to publication.

WPP's climate commitments versus its client roster

WPP has positioned itself as a leader on sustainability within the advertising sector. The group has pledged to reach net zero across its entire value chain by 2030, a target that encompasses not only its direct operations but also the work it performs for clients. The company reported £14.4bn in revenue for 2025.

The group's stated climate policy includes commitments to consider the environmental impact of the briefs it accepts. Yet the DeSmog findings suggest that, in practice, subsidiary agencies across the WPP network have continued to service major fossil-fuel accounts at a scale that exceeds the activity of competitor groups.

This is not unusual in the holding-company model. Large advertising conglomerates such as WPP operate through dozens of nominally independent agencies, each with its own client relationships, P&L responsibilities and, in many cases, local leadership teams. Policy set at the centre does not always translate into uniform behaviour at the edges of a global network.

The tension is familiar to anyone running a multi-entity professional-services business. A head-office commitment carries weight only if it is embedded in commercial decision-making at the subsidiary level, backed by governance mechanisms that can override local revenue incentives.

The net-zero timeline

WPP's 2030 net-zero target is ambitious relative to the sector. Achieving it would require significant changes not only to the group's own energy use and travel but also to the carbon intensity of the campaigns it produces and the clients it serves. The DeSmog report implicitly questions whether the target is compatible with continued large-scale fossil-fuel advertising work.

Regulatory and reputational exposure for UK service firms

The WPP case lands at a moment when regulatory scrutiny of green claims in advertising is intensifying on both sides of the Channel.

The UK Advertising Standards Authority (ASA) has tightened its guidance on environmental claims in advertising since 2022, issuing rulings against several energy companies for misleading green messaging. The Competition and Markets Authority (CMA) has likewise updated its Green Claims Code, setting out principles that apply to businesses making environmental assertions about their products or services.

Neither body currently regulates the internal climate policies of advertising agencies themselves. But the direction of travel is clear: organisations that make public sustainability commitments are increasingly expected to demonstrate consistency between those commitments and their commercial activities.

At the EU level, the Green Claims Directive is expected to impose stricter requirements on environmental marketing. Although the UK is no longer an EU member state, the directive is expected to apply indirectly to UK-headquartered firms serving European clients, according to legal analysis published by several City law firms.

For UK professional-services and agency businesses, the risk is not limited to formal regulatory action. Third-party investigative bodies such as DeSmog are filling a gap that regulators have been slow to occupy. Their reports carry media weight and can influence procurement decisions, talent acquisition and investor sentiment.

Investor and stakeholder pressure

ESG-focused investors have increasingly scrutinised advertising groups' exposure to fossil-fuel clients. While no major institutional investor has publicly divested from WPP on these grounds, the DeSmog report provides the kind of quantified, attributable data that shareholder resolutions and engagement campaigns typically draw on.

Board members at UK service firms should note that the enforcement of ESG policy is no longer the exclusive domain of regulators. It is being tested, publicly and with increasing sophistication, by civil-society organisations with access to commercial data.

What operators can learn from the policy-practice gap

The WPP case offers a practical lesson for leaders at UK service-sector businesses, particularly those operating through subsidiary or franchise structures.

First, publishing a climate policy is not the same as operationalising one. A commitment made in an annual report or sustainability statement creates a benchmark against which external actors will measure actual behaviour. If the policy is not embedded in client-acceptance procedures, incentive structures and subsidiary governance, it functions as a reputational liability rather than a safeguard.

Second, the holding-company model creates specific governance challenges. WPP's network includes agencies such as GroupM, Ogilvy and Mindshare, each operating with a degree of commercial autonomy. Ensuring that a group-level climate policy is applied consistently across such a network requires more than a memo from the chief executive. It requires changes to commercial processes, reporting lines and, in some cases, compensation structures.

Third, the definition of "value chain" matters. WPP's net-zero pledge covers its value chain, which logically includes the advertising campaigns it produces and the clients it serves. Firms that adopt similarly broad commitments should be prepared to defend them against scrutiny of their most carbon-intensive client relationships.

The gap between policy and practice is not unique to advertising. Any UK service firm that has made public climate commitments, and operates through a decentralised structure, faces a version of the same challenge.

Finally, the reputational calculus is shifting. A decade ago, fossil-fuel advertising work was commercially unremarkable. Today, it carries a measurable reputational cost, particularly for firms that have staked their brand on sustainability credentials. The DeSmog report quantifies that cost in dollar terms. For boards evaluating client-portfolio risk, the question is no longer whether such scrutiny will arrive, but when.

WPP's experience suggests that the answer, for many UK service firms, is sooner than expected.