Whenever some one visits Hacker News, where is Ycombinator "doing business" from? The country where the visitor is located? The country where the Hacker News moderators/programmers are located? The country where Ycombinator is headquartered? The location of the Hacker News servers? The location of the advertisers on HackerNews? If each country makes up their own tax rules to determine where Ycombinator is doing business, then a company may have to pay 200% of their total revenue in taxes to cover all the different locations that could claim business was being conducted there.

I think there is a single entity that determines allocation. Details TBD. It’s a one liner in the following doc;

https://www.oecd.org/tax/beps/statement-on-a-two-pillar-solu...

I just now read that... a lot of details to be worked out, and lot of opportunity for this to fail long before implementation.

It’s a back door federalization. Members will have to conform to additional TBD rules or put their tax allocation at risk.

I would be surprised if double taxation was not addressed or considered.