Just did some research on prerequisites for listing on the London Stock Exchange (LSE) and came across the following:-
Strictly speaking, minimum market cap is £700,000 but in reality it needs to be £100-£200m or more. At a bare minimum, if we were to list with a market cap of £100M, that would be app. $190M with our SOI of 2.4B gives us a share price of 8c - I think we all expect it to be greater than that on listing but it's reassuring to know that it will need to be at least that....
You can find that table at the following link if interested:-