If a trade is intended to influence the market it is called manipulation.
So if Missling is sending "Messages" by definition it is an attempt to influence and therefore manipulation.
Seldom see any prosecution for such things.
It would along the lines of wash trading which is also an attempt to influence the market.
Besides the purchase is part of a trading plan which means he has scheduled regular purchases in the future.
If you want to say that instituting the purchase plan is a message, OK. At these volumes (750 shares) it's not exactly a strong message. If it was 5K shares at a whack that would be different to me.