Technical audit · 2026-05-29

obi.de

German Home Improvement Retail Chain

A German home improvement retail chain. 388 requests, 21 domains. CloudFront. Usercentrics TCF serves as the CMP — but Kameleoon, Instana, GTM, and Bannerflow are all active before the banner. Four violations: two services undeclared (Instana, Bannerflow), two active without consent (Kameleoon visitorCode, GTM). Baqend SpeedKit and ot.obi.de — OBI's proprietary infrastructure.

Timeline of the leak

+120 ms · Instana, Usercentrics loader, Kameleoon

Three external services activate simultaneously with page load: eum.instana.io/1.8.1/eum.min.js (IBM RUM monitoring), web.cmp.usercentrics.eu/ui/loader.js (the CMP loader), l96jc26jvj.kameleoon.eu/engine.js (the A/B engine). Before the banner.

+131 ms · Baqend SpeedKit

obi-de.app.baqend.com/v1/speedkit/install.js — SpeedKit optimizes page loading, ML models (cl_desktop_xgb.json, cl_desktop_cfg.json), and a bloom filter. Six rum/pi requests follow throughout the session. Declared in the policy as technically necessary (§25(2) TDDDG).

+202 ms · Google Tag Manager

www.googletagmanager.com/gtm.js?id=GTM-5SDGHH — the tag container loads before the banner. Not mentioned in the policy.

+337 ms · Kameleoon visitorCode

eu-data.kameleoon.eu/visit/visitor?siteCode=l96jc26jvj — a request with currentVisit=true transmits visit data to Kameleoon SAS's servers. Followed at +1101 ms by visit/events, carrying visitorCode=r5rxxh2... and POST data.

+1442 ms · Bannerflow

c.bannerflow.net/scripts/responsive-format-v4.js (did=5cf6638e...) — the banner advertising platform. 19 requests: scripts, obi-baumarkt campaign data, fonts, image optimization. A tr/v2/pixel/ pixel (+2286 ms) fires before any interaction with Usercentrics.

Declared versus actual

✓ Kameleoon — declared as technically necessary (§25(2) TDDDG), 380-day retention — заявлен

✓ Baqend SpeedKit — declared as technically necessary (§25(2) TDDDG) — заявлен

✓ Usercentrics — declared as the CMP (§25(2) TDDDG, Art. 6(1)(c)) — заявлен

✓ Mapp Intelligence / Webtrekk — declared as anonymous tracking (§25(2) TDDDG) — заявлен

✓ Bonial — declared (§25(2) TDDDG) — заявлен

+ Instana / IBM (eum.instana.io, eum-blue-saas.instana.io) — not mentioned — не заявлен

+ Bannerflow (c.bannerflow.net) — not mentioned — не заявлен

+ Google Tag Manager (GTM-5SDGHH) — not mentioned — не заявлен

Transfer timings

+120 ms eum.instana.io

Instana EUM. IBM. Real User Monitoring. Not declared.

+121 ms l96jc26jvj.kameleoon.eu

Kameleoon engine.js. A/B testing. visitorCode.

+202 ms www.googletagmanager.com

GTM-5SDGHH. Tag container. Not declared.

+1442 ms c.bannerflow.net

Bannerflow. Banner advertising. tr/v2/pixel/. Not declared.

Detected trackers

Kameleoon (eu-data.kameleoon.eu) — A/B testing, visitorCode before consent
Instana / IBM (eum.instana.io, eum-blue-saas.instana.io) — APM performance monitoring
Baqend SpeedKit (obi-de.app.baqend.com) — RUM monitoring, rum/pi requests
Google Tag Manager (www.googletagmanager.com) — tag container
Bannerflow (c.bannerflow.net) — banner advertising platform
Usercentrics (web.cmp.usercentrics.eu et al.) — CMP

Indicators of GDPR non-compliance

GDPR Art. 5(1)(a); TDDDG § 25(1)
Kameleoon's engine.js (+121 ms) and a request to eu-data.kameleoon.eu/visit/visitor (+337 ms) carrying a visitorCode occur before the Usercentrics banner appears (+4636 ms). Kameleoon SAS (Offenburg) receives a visitor identifier without consent. The policy declares Kameleoon as technically necessary under §25(2)(2) TDDDG, but assigning a visitorCode with a 380-day retention period constitutes profiling, not a technical necessity.
GDPR Art. 13(1)(e); TDDDG § 25(1)
Instana EUM (eum.instana.io, eum-blue-saas.instana.io) loads and transmits data (+120 ms, +2165 ms, +4529 ms, +6593 ms) before and during the banner's display. IBM Instana is a Real User Monitoring tool. It is not mentioned in the privacy policy.
GDPR Art. 13(1)(e); TDDDG § 25(1)
Bannerflow (c.bannerflow.net) — a banner-advertising management platform — loads (+1442 ms) and sends a tracking pixel via tr/v2/pixel/ (+2286 ms) before the user interacts with the Usercentrics banner. Bannerflow is not mentioned in the privacy policy.
GDPR Art. 13(1)(e)
Google Tag Manager (gtm.js?id=GTM-5SDGHH, +202 ms) loads before the consent banner. GTM is not mentioned in the privacy policy, either under its own name or as a 'Tag Manager.'

Context

OBI is a German retail chain of home improvement and hardware hypermarkets, with 350+ stores across Germany. A subsidiary of the Tengelmann Group. CloudFront CDN, a Next.js-like architecture. HAR: 388 requests, 21 domains.

Usercentrics (the CMP) displays the consent banner roughly 4.6 seconds after the page begins loading. By that point, four external services are already active.

At +120 ms, Instana EUM (eum.instana.io/1.8.1/eum.min.js) loads — IBM’s Real User Monitoring tool. Over the course of the session, Instana transmits data to eum-blue-saas.instana.io three times. At +121 ms, the Kameleoon engine loads (l96jc26jvj.kameleoon.eu/engine.js). At +337 ms — a request to eu-data.kameleoon.eu/visit/visitor assigning a visitorCode, followed at +1101 ms by transmission of visit events carrying that identifier. At +202 ms, Google Tag Manager loads (GTM-5SDGHH). At +1442 ms, Bannerflow activates with a tracking pixel.

Kameleoon: “technically necessary” with a 380-day visitorCode

The policy declares Kameleoon as technically necessary under §25(2)(2) TDDDG and Art. 6(1)(f) DSGVO (legitimate interest). The stated rationale is “A/B Verteilung von Webseitenbesuchern zur Lastverteilung” (load balancing). However, the visitorCode=r5rxxh2up62t7vz7 parameter is retained for 380 days and transmitted to Kameleoon SAS’s servers in Germany. Load balancing does not require a long-lived visitor identifier.

Instana and Bannerflow: undeclared

Neither IBM Instana nor Bannerflow is mentioned in the privacy policy. Bannerflow is a Swedish banner-advertising management platform: 19 requests, including a tr/v2/pixel/ pixel, font loading, and obi-baumarkt campaign data.

Google Tag Manager: undeclared

GTM with identifier GTM-5SDGHH loads at +202 ms. The policy contains no mention of Google Tag Manager, Google, or a “Tag Manager” of any kind.

Baqend SpeedKit and ot.obi.de

Baqend SpeedKit is declared in the policy as technically necessary. It loads predictive-preload ML models (cl_desktop_xgb.json) and transmits RUM data via a series of rum/pi requests throughout the session. ot.obi.de is OBI’s proprietary endpoint for logging consent events (consent.viewed, onInitialPageLoad); it carries banner-state parameters (ess:true, mar:false, ana:false).

Conclusion

www.obi.de uses Usercentrics TCF as its CMP, yet four external services activate before the banner is displayed. Instana and Bannerflow are absent from the privacy policy. GTM loads without consent and is undeclared. Kameleoon is declared as technically necessary, but it assigns a long-lived visitor identifier.

Evidence

Original (audit)

HAR file: de/obi-de-2026-05-29.har

SHA-256: f69fdf09f65e74b018663d9a6a2ab06a49f6f415863f83f90f4f5317f7a6cc73

Re-check snapshot

Awaiting changes

HAR files are stored on EU infrastructure (Proton Drive). SHA-256 is published for integrity verification.

Ready-to-send complaint letter

Where to file: Federal Commissioner for Data Protection (BfDI) — file a complaint online →

To: Federal Commissioner for Data Protection (BfDI)
From: [Your name], [contact email]

1. Subject of the complaint
I am filing a complaint regarding the processing of my personal data by the website obi.de.

2. Circumstances
I visited the website obi.de and found indications that the processing of my personal data does not comply with the GDPR. The technical analysis published on gdpru.eu on 29 May 2026 (open methodology, reproducible measurements) documents the following indications:

1) Kameleoon's engine.js (+121 ms) and a request to eu-data.kameleoon.eu/visit/visitor (+337 ms) carrying a visitorCode occur before the Usercentrics banner appears (+4636 ms). Kameleoon SAS (Offenburg) receives a visitor identifier without consent. The policy declares Kameleoon as technically necessary under §25(2)(2) TDDDG, but assigning a visitorCode with a 380-day retention period constitutes profiling, not a technical necessity.

2) Instana EUM (eum.instana.io, eum-blue-saas.instana.io) loads and transmits data (+120 ms, +2165 ms, +4529 ms, +6593 ms) before and during the banner's display. IBM Instana is a Real User Monitoring tool. It is not mentioned in the privacy policy.

3) Bannerflow (c.bannerflow.net) — a banner-advertising management platform — loads (+1442 ms) and sends a tracking pixel via tr/v2/pixel/ (+2286 ms) before the user interacts with the Usercentrics banner. Bannerflow is not mentioned in the privacy policy.

4) Google Tag Manager (gtm.js?id=GTM-5SDGHH, +202 ms) loads before the consent banner. GTM is not mentioned in the privacy policy, either under its own name or as a 'Tag Manager.'

Full technical documentation is published at: https://gdpru.eu/en/audits/de-obi-de/

3. Provisions violated
GDPR Art. 5(1)(a); TDDDG § 25(1); GDPR Art. 13(1)(e); TDDDG § 25(1); GDPR Art. 13(1)(e); TDDDG § 25(1); GDPR Art. 13(1)(e)

4. Request
I request that you investigate the violations described and apply the measures provided for in Article 58(2) GDPR.

5. Attachments
The full evidence base — the HAR file, its SHA-256 checksum and the quotation from the site's privacy policy documenting the stated contradiction — is published and verifiable at the link in point 2 above.

[Date]                                    [Signature / name]