I'm not a securities lawyer, but it would be unbelievably risky for Sheldon to sell his shares knowing that impending negative news was coming. I don't think he would be that stupid, so soon after he left the BOD, regardless of what his actual knowledge is. With his selling being so close to his departure, if negative news came out, his transactions would automatically come under scrutiny. Selling right now with even a hint of bad news would be reckless.

My opinion, but I think he either has no relevant insider information or he knows that any news that comes out in the short term would not be viewed as negative.