My understanding of this from a securities lawyer friend is that if a board or executive has information that activley would be a material change to the company he/she could open themselves and the company to a lawsuit for trading on non-public information. The threshold is generally about 10% of revenues. For a company like Coke or JPM it doesn't hit that threshold even if its important. For small startups or companies like Syncora it would be hard to state they were not aware. Correct or not but I'd bet their legal council has advised them not to unless its part of a plan bought monthly by a trust not managed by them.
Is this always done. Absolutely not but when part of your cases against the big boys is that you are pious it could be used against you. Secondly, psycologically its hard when your income is 100% from the company and then you are spending that money to increase your exposure. Many people even if they are 100% confident have trouble with that lack of diversification.
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