Yes, 70% premine. Absolutely unethical
https://blog.ethereum.org/2014/07/22/launching-the-ether-sal...
I.e. it was a crowdsale raising funds for development, much like projects on Indiegogo except that it was a nonprofit instead of a business.
I hope you can see why many people believed the US was prohibited.
There was serious concern that the Ethereum Foundation would get in trouble with the SEC if they sold in the US. They delayed the crowdsale for several months while they consulted lawyers, who finally signed off on a way to keep them out of SEC trouble. There was a lot of discussion about this in the community.
The presale was open for 42 days and very well known in the crypto community. Within the first few days it was clear that it was going to be one of the largest crowdsales to date, so it got regular media attention too.
Once they've finished selling their premine to the public would it be accurate to say it wasn't premined at all? Of course not. So it's not accurate to exclude the partially sold portion now.
This massive understatement of their premine is a well known example of the dishonesty of ethereums operators and advocates.