I guess the difference is that you and I can sell our shares at...

I guess the difference is that you and I can sell our shares at any time without consequence. Need a bit of extra cash? Just sell a few shares.

When a CEO starts selling shares then alarm bells ring and often prices quickly fall.

If Tim wants to actually realise the value of his shares anytime soon then a takeover is probably a pretty good result for him. Otherwise he has to wait for dividends before he can enjoy the benefits of his holdings.