I don't think it makes sense to apply "total_valuation = microsoft_price / microsoft_stake". There are a load of wishy-washy things Microsoft could be looking t

I don't think it makes sense to apply "total_valuation = microsoft_price / microsoft_stake". There are a load of wishy-washy things Microsoft could be looking to get out of this - a seat on the board, knowledge, position, credibility, yada yada... I doubt they're in it to make a direct return on their $240 million investment. You could probably add or subtract $100,000,000 or 1% from the figures involved and it wouldn't affect whatever Microsoft's trying to do.