> aggregate market cap will only increase by $50B
If you list 5% of a $1 trillion company on a stock exchange, the aggregate market capitalisation goes up by $1 trillion. (Float goes up by $50bn.)
Market capitalisation is price per share times shares outstanding [1]. Float is price per share times publicly-trading shares [2].
[1] https://www.fool.com/investing/small-cap/2005/04/29/quotouts...