Table of content
In Brief: The Results (90 Days)
Total requests saved: 217,332 hits (that would have been blocked or limited).
Sales Impact: 30.7% of purchases recovered (AdBlockers + ITP).
Safari Impact: 100% of Safari traffic protected against cookie deletion (ITP).
1. The Context: A Premium Market Dominated by iPhone
Vaudvins.ch is a reference for online wine sales in Switzerland. When it comes to "Wine" in Switzerland, it often means a clientele with high purchasing power. And when we talk about purchasing power, we talk about... Apple.
By analyzing their traffic, the conclusion was clear: a massive share of visitors use Safari (on iPhone and Mac). However, since the implementation of ITP (Intelligent Tracking Prevention) by Apple, Safari has become the worst nightmare for marketers: tracking cookies are deleted after 7 days (or even 24 hours).
The Problem: A customer discovers a Grand Cru on a Facebook ad on Monday. They think about it. They return to buy the following Tuesday.
Without Server-Side: Safari has deleted the cookie. The sale is attributed to "Direct". The Facebook ROAS is incorrect.
With AdBlocker: The sale isn't even seen by Google Analytics.
Vaudvins.ch was managing its campaigns with truncated data.
2. The A-Track Intervention: Opening the "Black Box"
To counter this loss of signal, we deployed our proprietary Server-Side Tracking infrastructure. Instead of letting the client's browser decide the fate of the data, we routed the streams through a secure server (Proxy) controlled by Vaudvins.
Here’s what the data revealed over a period of 90 days after installation.
3. Analyzing the Results: The "Hidden Side" of Performance
The figures below come directly from the comparison between the "Client" stream (blocked) and the "Server" stream (recovered).
This is the most critical statistic for Revenue. On the Purchase event, we found:
5.54% of sales recovered from AdBlockers.
25.20% of sales recovered from Tracking Prevention (ITP Safari/Firefox).
The Business Insight: Without this intervention, 30.7% of actual sales were either invisible or misattributed in analytics tools. Imagine managing your marketing budget while ignoring 1 in 3 sales!
B. Safari: Reclaiming Mobile Traffic
The report shows that 185,546 requests were "saved" from tracking prevention mechanisms. Interestingly, this almost exactly corresponds to the total volume of Safari traffic during the period.
This means that 100% of Safari users were previously constrained in their tracking (short-lived cookies). Thanks to Server-Side, Vaudvins restored a cookie lifespan (First-Party) of several months, finally allowing them to measure the Customer Lifetime Value (LTV) of their iPhone customers.
C. The "Clogged" Conversion Funnel
The data loss affected not only the final purchase but the entire journey:
ViewCart: 31.79% of data recovered.
AddShippingInfo: Up to 100% impact on certain segments.
By recovering this intermediate data, Vaudvins can now create much larger and more precise retargeting audiences (Abandoned Cart).
4. Consent Management: The Reality of "No"
Compliance with nFADP requires respect for user choice. On Vaudvins.ch, consent rates are clear:
PageView: 37.8% refusal (Opt-out).
Purchase: 15.4% refusal.
Note that buyers (Purchase) are more willing to accept cookies than casual visitors.
The Power of Advanced Mode: Thanks to the implementation of Google Consent Mode v2 via Server-Side, Vaudvins does not completely lose these 37% of "Refusal" visitors. Google Analytics 4 uses these anonymized signals to model the behavior of missing users, filling gaps in acquisition reports.
Conclusion: Don't Let Apple Decide Your ROI
This case Vaudvins.ch is representative of Swiss e-commerce in 2026. If you have a CSP+ clientele (Apple users) and you don't have Server-Side tracking, your Analytics reports are 30% inaccurate.
You are not losing sales, but you are losing the intelligence that allows you to generate new ones.
Do you want to know how many sales your site is "missing" in its reports?
Let's conduct the same audit for your e-commerce.