So basically you are saying the consultant can never sell their shares, why would anyone take shares for compensation if they can never sell them?
And no, just because you work for a public company doesn't subject you to insider trading rules, again I could buy/sell stock for the company I worked for and I was in the finance department, there were certain events that would trigger insider trading, otherwise I was free to trade so long as there was not a blackout period in effect.
People outside of Finance had even more flexibility in selling their shares.
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