So I’ve been reading my way through the fantastic introductory wiki. Lots of questions come to mind (I’ll be back!), but I was wondering about this line from What Even Is a Stock?:
In an IPO, the current private owners aren’t necessarily selling their shares — in fact, often they legally can’t for some time.
I’d naively assumed that in the event of, say, Freetrade IPOing, then all the original investors would be bought out - with any tax liabilities that that entails. I’m now assuming that’s not the case - and the private shares can be translated to listed ones. Is that right? If so, is there a tax implication for this transfer? Would you be able to wrap the newly listed shares in an ISA, for example - or would you need to sell them first? On the timing issue, does anyone have any insight about why private owners might be prohibited from selling shares? Would this be agreed / voted on as part of the prep for IPO? Maybe to ensure share price stability? 
(Also, random probity question: would the Freetrade platform be able to trade Freetrade stock, assuming that it’s listed on, say, AIM? Are there any conflict of interest issues? I’m assuming not, but it crossed my mind and I’m curious! 
)