Now - if he starts huffing and puffing about easy2 - the Sequel - the other investors may well take fright, and start off loading their shares. Stelios has 38%. Let's assume one of his buddies has 10%. Get the other investors to sell, get the share price down, buy 3%, hey presto, it's his airline again. Then announce that the whole fast jet thing is a smokescreen, 'I looked at it in some depth and it wasn't the thing to do' etc etc, let it die a death.
No can do.
Acting with someone who has 10% would be classified as acting "in concert" and is illegal and will get someone a nice big fine, its why Stelios's family holding are viewed as being all together.
Other sanctions including facing other shareholders as they sue for damages in a civil court claiming their shareholding has been devalued as other shareholders acting to buy their shares on the cheap.
In addition he cannot buy anymore shares, once you have 29.9% to buy any more shares you have to launch a formal takeover for all shares at a set price.
Ok he has 38% but that was because he has sold off his shareholding rather than buying more.