Made for advertising (MFA) sites exist to sell ads, not to serve readers. On September 26, 2023, the ANA, the 4A’s, the World Federation of Advertisers (WFA) and ISBA published a shared definition: MFA sites usually show some mix of five traits. The ANA’s June 2023 study found MFA sites made up 21 percent of the impressions and 15 percent of the ad spend it examined.
How do the ANA, 4A’s, WFA and ISBA define an MFA site?
The definition says MFA sites usually show some combination of these traits:
- High ad-to-content ratio. Usually at least twice the internet average, for example 30 percent or more on desktop.
- Rapidly refreshing ads. Numerous refreshing banners, autoplay video, and slide shows that make visitors click through many pages.
- Heavy paid traffic. Little organic audience. Visits come from clickbait ads on social networks, content recommendation platforms and sometimes reputable publishers’ sites.
- Generic content. Templated, low-quality, often syndicated, dated and non-unique.
- Poor, templated design.
The release gives the economics. Buying paid traffic is the main cost of running an MFA business, so these publishers lean on aggressive monetization and arbitrage to cover it. The 4A’s also call these Made for Arbitrage sites.
The same release adds the awkward part: MFA sites tend to show high measurability, good viewability and low invalid traffic, and they are usually brand-safe. Standard quality metrics will often score them well.
What did the 2023 ANA study find?
The ANA Programmatic Media Supply Chain Transparency Study, released June 19, 2023, analyzed log-level data from 21 ANA member companies. It covered $123 million in open web programmatic spend and 35.5 billion impressions between September 2022 and January 2023.
Within that sample, MFA sites accounted for 21 percent of impressions and 15 percent of spend. The average campaign ran on 44,000 websites, counted as top-level domains.
MFA was one finding in a wider report that put as much as $20 billion, or 23 percent, of the $88 billion open web programmatic market down to waste. It was also the first of two report segments, and the second was to cover ad quality, pricing, viewability, measurability and ad fraud.
The ANA’s advice was to exclude MFA sites unless they are specifically wanted, to test them against brand suitability standards, and to state a tolerance for MFA inventory.
What does the 2026 benchmark say?
The ANA’s Q1 2026 Programmatic Transparency Benchmark, released May 27, 2026, reports MFA exposure of 1.1 percent in Q1 2026. That is up from a range of 0.4 to 0.6 percent through 2025, and the report names AI slop as an emerging subtype. The market-level TrueAdSpend Index, the share of programmatic spend delivering fraud-free, measurable, viewable and MFA-free impressions, was 43.3 percent.
The index rebounded after volatility in late 2025, and the ANA ties the recovery mainly to better delivery quality, especially viewability, rather than lower costs. The same release says higher-performing advertisers converted 54.0 percent of spend into qualified impressions in Q1 2026, against 32.1 percent for the lower-performing cohort. The benchmark draws on log-level data across web, mobile and CTV, with participating marketers rising from 54 to 86 and 66 active contributors.
| Study | Period | Participants | MFA figure |
|---|---|---|---|
| 2023 study | Sept 2022 to Jan 2023 | 21 ANA members | 21 percent of impressions |
| 2026 benchmark | Q1 2026 | 86 marketers | 1.1 percent exposure |
The two figures are not a trend line. The participants differ, one is a fixed study window and the other a quarterly benchmark, and the release does not define how MFA exposure is measured. Read each on its own terms.
What does this mean for a buyer?
The definition describes traits, not a list. Applying it means choosing which traits you will tolerate and keeping an exclusion list current. Path Check supports made-for-advertising exclusion lists and shows the DIRECT or RESELLER relationship behind every placement, so a buyer can see who sells a flagged site and by what route.
Because MFA sites often measure well, decide on MFA exclusion separately from viewability and invalid traffic checks.