I suppose a percentage based on multiple factors could work. Like, just spitballing numbers here.
- 50% would be based off of ownership. If the ownership is completely european, the product gets 50%
- 50% would be based off of manufacturing location. If 80% of the product is from Europe, then the product gets 80% of 50%, so 40%.
- Final score, 90% european. Label the product with this percentage, and you'll possibly have an advantage over your competitor if your percentage is higher.
It would however be quite expensive to make the documentation for every single product sold, but Denmark already requires something more convoluted and detailed with construction materials and environmental impact, so I suppose it wouldn't be impossible to implement. Just a matter of will.
Edit. Fucked up the percentage stuff a bit, made it make sense.
Nothing surprising really. Hopefully when people start to die at a high rate from completely preventable diseases and start getting sick from poor food quality, they realise what has to happen to fix it.