A white paper from the German digital trade body BVDW, announced on October 22, says affiliate touchpoints are visible in 12.41% of transactions under last click, while affiliates took part in 24.92% of them. The BVDW affiliate attribution figures cover 185 advertisers in Q1 2026. The paper’s pragmatic option, a position-based 40/20/40 view next to last click, is not among GA4’s attribution models: Google lists position-based attribution as no longer available as of November 2023.
What did the BVDW affiliate paper find?
Under last click, affiliate touchpoints are visible in 12.41% of transactions, while affiliates are involved, with at least one touchpoint, in 24.92% of the transactions analysed. The data covers 185 advertisers, comes from tracking by attriXus, easy Marketing and Ingenious Technologies, and was collected in Q1 2026. The paper’s word is „beteiligt“ (our translation: involved): a transaction counts once at least one affiliate touchpoint appears on its journey. That is participation; the paper does not show that the touchpoint caused the sale.
The authors read it more strongly. In the PDF they write: „Der tatsächliche Beitrag liegt damit Faktor zwei über dem sichtbaren Beitrag“ (our translation: the actual contribution is thus a factor of two above the visible one). Both numbers are shares of transactions: one counts where an affiliate touchpoint is visible under last click, the other where any affiliate touchpoint appears. Neither is a share of revenue credit.
PPC Land covered the paper in English on October 24. It notes how little the paper says about the 185 advertisers, and it raises three points that we checked against the documents. The seven named authors work at Artefact, digitAL Consultancy, Webgains, uppr, MAI xpose360, impact.com and AdCell. The announcement lists Annalena Bauer, the APMC deputy chair, with easy Marketing, one of the three data suppliers, while the PDF author list gives digitAL Consultancy. And the imprint, dated Berlin, September 2026, ends with „Dieses Paper wurde unter Verwendung von Künstlicher Intelligenz angefertigt“ (our translation: this paper was produced using artificial intelligence).
Can GA4 show the 40/20/40 view the paper recommends?
Not as a built-in model. The paper keeps last click for commission payouts, because it is „eindeutig und manipulationsresistent“ (our translation: unambiguous and manipulation-resistant), and suggests a second view for steering, naming as the pragmatic option „Position-based mit 40/20/40-Gewichtung parallel zum bestehenden Reporting“ (our translation: position-based with 40/20/40 weighting, in parallel with existing reporting). Google’s help page on attribution settings says: “The first click, linear, time decay, and position-based attribution models are no longer available as of November 2023.”
Google’s attribution overview lists three models in the Attribution reports: data-driven, paid and organic last click, and Google paid channels last click. So a 40/20/40 split has to be computed outside GA4’s attribution models. Inside GA4 the comparison on offer is data-driven against last click. Switching between them moves credit between channels; it does not count how many transactions an affiliate touched.
Our earlier piece on multi-source conversions and GA4 imports covers a related line from Google: for that feature, merging and deduplication of conversions tracked in Google Analytics “must happen within Google Analytics itself before the data is imported into Google Ads.”
Where the 68% comes from
The paper’s most GA4-specific number says 68% of the discrepancies between GA4 and affiliate networks come from different attribution models. Its footnotes trace this to the MAI xpose360 and AffiliateBLOG.de Trend-Report, published in January 2026: 1,200 respondents plus 42 expert assessments. The cited source is a survey report, not a reconciliation of GA4 and network data. One of the paper’s authors, Daniel Kocher, works at MAI xpose360, a connection PPC Land also notes.
The table below lists the figures from the paper that readers are most likely to quote, with what each one measures.
| Number | What it measures | Source and base |
|---|---|---|
| 12.41% | Transactions in which affiliate touchpoints are visible under last click | Paper, section 3.1; 185 advertisers, Q1 2026, three tracking vendors |
| 24.92% | Analysed transactions with at least one affiliate touchpoint (participation) | Same sample and vendors |
| 68% | Share of GA4-versus-network discrepancies attributed to different attribution models | MAI xpose360 Trend-Report, January 2026; survey of 1,200 plus 42 expert assessments |
| 39% | Advertisers using no specific method to measure incremental revenue | MAI xpose360 Trend-Report, January 2026 (survey; paper footnotes 9 and 40) |
| 33% | German advertisers using customer journey tracking in 2026 | MAI xpose360 Trend-Report, January 2026 (survey; footnote 34); the appendix calls the factor-two gap a direct result of this thin data base |
| 83% | Expectation that server-to-server tracking is standard, not adoption | Paper, section 6.2; MAI xpose360 Trend-Report, January 2026 (survey; footnote 27) |
| €932m | Invested in affiliate and partner marketing in Germany, 2025 | APMC market survey (May 2026); data reported by 13 networks and platforms active in Germany |
What to check in your own setup
Start with the channel itself. Google’s default channel group table gives the Affiliates rule as “Medium = affiliate”. A network click without that medium is not counted as Affiliates, so tag network links consistently before comparing any GA4 number with a network report. We described how the same channel group classifies other sources in GA4’s AI Assistant channel.
Then keep presence and effect apart. Participation tells you where affiliates appeared; it does not tell you what they added. The paper points to incrementality tests for that, and we covered what an exposed-versus-control design looks like in another channel. Until such a test has run on your own programme, treat 24.92% as a presence figure from 185 advertisers, not as a rate to apply to your own account.