The evidence standard is whether the four rings still make the business easier to understand. The mark began as architecture, but it has to keep pointing to product discipline, more than merger history.
Symbol proof starts with compression. A customer should read unity quickly without needing to memorize Audi, DKW, Horch, and Wanderer before the brand makes sense.
Product proof keeps the symbol alive. Engineering language has to appear in drive, cabin, design, safety, electric transition, service, and ownership confidence.
Heritage proof should serve current preference. Auto Union memory matters when it explains a discipline customers can still see in the car.
A useful check would inspect mark use, model architecture, technology claims, design system, and customer-facing service. If the product story is weak, the rings become a history badge.
The decision lesson is that merger symbols need ongoing evidence. A mark can simplify architecture, but it cannot produce coherence that the product range refuses to support.