Digital audience measurement: How gatekeepers weaponize opacity

Digital advertising spending has reached unprecedented levels, with large platforms capturing most of the growth. But behind this success lies a concerning pattern: major tech companies are systematically resisting independent measurement of their advertising effectiveness, preferring instead to "grade their own homework."

A month after releasing their influential research paper in February 2025, legal experts Thomas Höppner and Philipp Westerhoff have exposed how digital gatekeepers leverage opacity in audience measurement systems to maintain market dominance. Their analysis reveals how platforms like Google, Meta, and Amazon have created information asymmetries that harm advertisers, competitors, and media plurality.

The critical role of audience measurement

Independent audience measurement serves as the foundation of the media and advertising ecosystem. According to the European Media Freedom Act, audience measurement is defined as "the activity of collecting, interpreting or otherwise processing data about the number and characteristics of users of media services or users of content on online platforms for the purposes of decisions regarding advertising allocation, pricing, purchases or sales or regarding the planning or distribution of content."

For decades, advertisers relied on neutral third-party measurement to compare advertising effectiveness across different media channels. This transparency enabled informed budget decisions and fostered fair competition among media owners. Joint Industry Committees (JICs) - non-profit organizations representing advertisers, media owners, and agencies - emerged to develop impartial benchmarks for measuring ad performance.

"Audience measurement is of key importance for the media and advertising ecosystem, being the core tool for understanding the market dynamics, calculating advertising prices, allocating advertising revenue, and planning the content production in accordance with the preferences of the audiences," the European Commission stated in its impact assessment for the European Media Freedom Act.

The rise of walled gardens and proprietary measurement

Despite the established role of JICs (Joint Industry Committees), major digital platforms have consistently refused to participate in independent measurement. As Höppner and Westerhoff explain, "Google and Meta, in particular, have steadfastly refused to allow established JICs to measure the usage of their platforms, in particular Google Search, YouTube and Facebook, on the basis of their industry standards."

Instead, these platforms have created "walled gardens" - closed ecosystems where they exercise complete control over data collection, ad scheduling, content delivery, and audience measurement. While they might cooperate with selected measurement vendors, these partnerships involve providing only aggregated data originally captured by the platforms themselves, making true verification impossible.

According to the European Media Freedom Act, certain new players "do not abide by the industry standards or best practices agreed through industry self-regulatory mechanisms and provide their proprietary measurement services without making available information on their methodologies."

The consequences of weaponized opacity

This lack of transparency creates multiple harms:

Harm to advertisers

Without transparent measurement, advertisers cannot properly evaluate ad efficiency, leading to:

1. Ad waste: Platforms have been known to charge for ads even when just one pixel entered a screen for a millisecond. According to Marc Pritchard, quoted in the Journal of Marketing, when advertisers discovered the actual view times, they "shifted substantial spending away from static digital display ads and into more effective media."
2. Excess frequency: Platforms charge advertisers for showing the same ad to the same person multiple times, without allowing advertisers to properly limit frequency.
3. Ad fraud: A comprehensive study estimated that in 2023 alone, $84 billion in digital advertising investment was lost to ad fraud - 22% of all online ad spend. This figure is expected to more than double by 2028.
4. Hidden auction manipulations: Court findings confirmed that Google had manipulated auctions for search ads to "raise prices without telling advertisers about it."

Harm to competition

Self-preferencing in measurement distorts competition in several ways:

1. Influencing budget decisions: Gatekeepers use proprietary audience measurement to present their ad channels more favorably, attributing conversions to their platforms even when other media played a more significant role.
2. Over-attribution: Platforms claim credit for conversions they had little influence on. As one expert explained, "Marketers have grown accustomed to its self-fulfilling prophecy, wherein conversion-optimized ads are tailored to individuals predisposed to certain actions, leading to inflated campaign performance metrics."
3. Cross-media expansion: Google, Meta, and other platforms are now attempting to expand their measurement dominance across all media through initiatives like the "Halo Cross Media Measurement" framework, potentially extending their biased methodology to TV and print.

Harm to media plurality

The opacity in digital audience measurement ultimately threatens media plurality and democracy itself. Without independent verification, ad spending can inadvertently fund unsuitable content, while quality journalism loses revenue. According to the World Economic Forum, disinformation represents one of the greatest threats to the global economy.

Regulatory and industry responses

Several initiatives attempt to address these issues:

1. European Media Freedom Act: Article 24 requires audience measurement systems to comply with principles of transparency, impartiality, inclusiveness, proportionality, non-discrimination, comparability, and verifiability.
2. Digital Markets Act: Contains provisions to increase transparency in online advertising, though it doesn't directly address self-preferencing in audience measurement.
3. Industry initiatives: Some advertisers are pushing for a return to independent measurement standards, although gatekeepers' market power makes this challenging.

The path forward

Höppner and Westerhoff suggest several policy recommendations:

1. Strengthening Joint Industry Committees: Making participation in JICs mandatory for digital gatekeepers would ensure independent measurement based on industry standards.
2. Structural separation: Obliging gatekeepers to divest their measurement services would remove conflicts of interest and create transparency.
3. Antitrust enforcement: Both standardization agreements and unilateral conduct relating to audience measurement should face increased scrutiny.

"Without an independent measurement, there is also no independent media," the authors conclude. Creating transparent, trustworthy audience measurement is essential not just for market efficiency but for preserving media plurality in democratic societies.

Timeline

• 1914: First Joint Industry Committee established in Chicago to "put a stop to circulation liars"
• 1960s: JICs expand across Europe for print, radio, and television measurement
• 2000s-2010s: Digital gatekeepers resist participation in established measurement systems
• 2020: World Federation of Advertisers launches initiative for cross-media measurement
• 2022: Digital Markets Act introduces transparency obligations for ad platforms
• 2024: European Media Freedom Act enters into force
• February 2025: Höppner and Westerhoff publish research on weaponized opacity in audience measurement
• March 2025: Major platforms capture more than half of all advertising spend outside China