ART+COM's patent was invalidated in 2017 due to prior art from another app called TerraVision from SRI shown in 1994.

If you trust the guys involved (and I do because they have a great track record within the German hacking community) the story goes as follows: This invalidation was carried out by a jury who had no clue what they were doing, after the first judge (coincidentally married to a google lobbyist) pulled back frommthe case which was running rather well for them.

I just spent 3 hours on listening to a (German) podcast on the matter with one of the people who developed the algorithm that was copied (addressing scheme for storing and adressing the different LOD tiles in memory, coincidentally the exact scheme Google uses till today, because the guys spent a lot of time optimizing).

The prior art TerraVision had the same name but was a completely different software (military simulation if I understood correctly) and didn't make use of that algorithm.

They still convinced the jury : )

The referenced podcast episode:

https://cre.fm/cre222-terravision

A thanks for adding that, I somehow forgot to add it myself.