Without more details the whole story sounds iffy. Since he did not give us more details but still shared his story I will speculate that he took advantage of what he thought were some clever tax loopholes in MA. Remember that hid did state very passingly that he has a presence in MA. Specifically this:

>>Again, I hadn't lived there or worked there since 2003, but I did own part of a business that was headquartered in MA, and the state was using this fact to harass me for income tax money<<

So in essence, he probably took advantage of some iffy tax loop hole which the state now probably disagrees with and is asking for whatever it thinks it is owed.