Just when I thought I was getting the hang of how equity works... I didn't understand a word of that (other than non-transferable exercised options).
Someone lends you money to exercise your options, you pay them back (at IPO or acquisition) as well as additional compensation for their risk of your shares being worthless.
There is a lot of uncertainty about whether these loan-and-pretend or forward structures violate the spirit of one’s stock option contract, which can and has resulted in forfeiture, and if it involves creating an off-exchange securities swap, illegal since Dodd Frank for non-qualified participants. It was receiving regulatory attention before cryptos distracted everyone. (One firm even got jammed by the SEC early on for structuring illegal swaps.)
Post-IPO the shares are prob deposited in Computershare and as a shareholder you can transfer it to anyone you want.