Every right of first refusal clause I've ever been subjected to or subjected others to has had a thirty day deadline, so I don't think this is accurate. It's unlikely that the set of companies I worked for / founded was that unrepresentative.

Mind you, when I did do a sale on the secondary market, it always took the full thirty days for the company to approve.

That seems like a pretty lame loophole. Is that the crux of the method for preventing secondary markets?

That may be standard, I'm not really sure, just remember everything is negotiable.