Their own white paper (no longer hosted on their site it seems) says they created 250 million tokens and pre-sold 37.5 million.

https://mixin.one/assets/MobileCoin-Whitepaper-EN_FINAL.pdf

This whitepaper is not the whitepaper I wrote back in 2017. We took that down because it was ultimately not the design we implemented. The full system design can be found here: https://github.com/UkoeHB/Mechanics-of-MobileCoin/blob/maste....

Fyi, while the whitepaper marcinzm links to may not be the design you implemented, it is the first result (for me, at least, in the UK) when googling "MobileCoin Whitepaper", while the Mechanics of MobileCoin repo doesn't appear at all.

Just in terms of avoiding confusion, you might want to reach out to mixin.one to try to replace that document with one that clarifies that the design outlined there was not used? Or publicise the actual design a bit better? (I couldn't find a link to this repo on the MobileCoin website, which is why I searched for the whitepaper elsewhere in the first place).

It's in the whitepaper. There are 250 million coins in total, and 37.5 million were sold in the ICO. I couldn't find any information on further distribution or monetary policy, so I assume the founders still hold them.