Tasty
Sounds like the danish plates called "reduced tax commercial plates" here on platemania. In danish they're called "papegøjeplader", meaning "parrot plates" because of the multi-coloured background.
These plates get a tax reduction, but not as big as for standard commercial plates. The difference is, that the "parrot plates" can be used by private individuals, whereas the the full blown commercial plates can only be used for work relaated tasks.
Reminds me of a fun story. Back in the late 1950s, you could be a special car in Denmark. it was called Opel Caravan Combi. It was an Opel Rekord P1 Caravan where the rear windows had been removed and replaced by metal panels, but the rear seat was still there. So it was actually a P1 Delivery Van, but with rear seats.
Now, the fun part is, that this car was intended to be registered on "parrot plates" and the buyer was allowed to use it as a passenger car from day one, BUT he had to wait 5 years before re-installing the removed rear windows and re-registering the car on regular plates. So for 5 years, the family could go for rides through the countryside, and the kids would sit in the back staring at those metal panels, cursing daddy for waanting to save some money on taxation!
Nice story
Here in Norway you can have the green plate, we just call it "varebil" due to the lack of rear seats. A privat person like me can go and buy a car like that, so that doesn't make it commercial. However, companies can also do and buy the exact same car, kinda making it commercial.
When you buy it you reduce some kind of tax, making it often pretty cheaper to get it with only 2, or in some cases 3 seats rather than 4 + seats. It's not reduced as much as with a black plate, but I have little knowledge about this due to it being extremely rear..
All in all, it's cheaper to get a car on green plates, BUT, it does not make it commercial or tax exempt. PlatesMania don't have a 100% accurate representation of the plate, but tax reduced would probably have been the more correct term.