He's worth a lot more than $20m so he could invest a lot anytime...

He's worth a lot more than $20m so he could invest a lot anytime he likes but I believe the main reason he doesn't buy is that he gets a huge amount of satisfaction from acquiring his wealth when it's based solely on his own skill and effort.

That's one reason why he has always insisted that most of his remuneration be "at risk" and linked to performance milestones; in other words, a low base salary and a fair whack of shares and oppies. You could say that he's the opposite of the typical fat cat corporate type. So he only becomes wealthy when ALL shareholders become wealthy.

The other motivating factor is his personal friendship with Dr Mark Hart. Those two go back a long way and have always been there for each other when a helping hand was needed. He'll been keen as mustard to see Dr Hart succeed with this and succeed big-time.