Walled Garden

/wɔːld ˈgɑːdn/

A walled garden in digital advertising is a closed ecosystem controlled by a platform owner, limiting access to data and ad performance metrics. Big players like Google and Facebook operate as walled gardens, offering large user bases but limited transparency.

How Walled Gardens Work

Unlike the open web, walled gardens like Facebook, Google Ads, and Amazon Advertising are self-contained advertising ecosystems. Advertisers must use the platform’s tools and data, which aren’t interoperable with the open web, creating data fragmentation and cross-platform tracking challenges.

The Benefits and Challenges of Walled Gardens

Walled gardens offer powerful advantages to advertisers, but they also come with significant limitations.

Advantages:

  • Unmatched Audience Data: Platforms like Google and Facebook collect vast amounts of first-party data, allowing advertisers to precisely target users based on demographics, interests, and behavior.
  • Fraud Prevention & Brand Safety: Since these platforms control their ecosystems, they have strong measures against ad fraud and inappropriate content placement.
  • Seamless User Experience: Ads are integrated directly into platform experiences, making them more engaging (e.g., Instagram Stories Ads, YouTube Pre-roll Ads).

Challenges:

  • Limited Data Access: Advertisers only receive performance insights that the platform chooses to share, restricting independent analysis.
  • Higher Costs: With limited competition inside walled gardens, advertisers often face higher ad prices compared to programmatic advertising on the open web.
  • Lack of Cross-Platform Attribution: Since data cannot be easily shared across platforms, tracking a user’s journey across multiple walled gardens is difficult, making attribution modeling complex.

As the privacy-first era emerges, walled gardens have become even more dominant due to their access to first-party data. With third-party cookies being phased out, advertisers rely more on platforms like Google and Facebook to reach their audiences effectively.

Walled Gardens vs. Open Web

FeatureWalled Gardens (Google, Facebook, Amazon)Open Web (Independent Publishers, SSPs)
Control Over DataFully controlled by platformShared across multiple ad tech providers
Audience TargetingFirst-party data, highly preciseLess precise, relies on third-party data
TransparencyLimited reporting & insightsGreater data access for advertisers
CompetitionAdvertisers bid within the platformMultiple ad exchanges and networks compete

While walled gardens provide advanced tools for advertisers, many brands and agencies balance their ad spend between these platforms and the open web to diversify their reach and improve transparency.