He didn't have to sell, but if he didn't he would have had to cough up a cool $2.7 million to pay for the shares from the exercise.
That's a reasonable explanation for the 200,000 excercise/sell. I was trying to determine what you thought the reason was for the 400,000 share "planned" sale. By your calculations that would be an additional cool 5.4 million sale, not required to pay for the shares from the excercise.
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