Counting what he already owns and what he will get by options that is only a smallish percentage of his holdings. Assuming that Arcam is most of his wealth , any financial planner would tell him to diversify. Because once he has a few tens of millions of dollars he has enough to hide some way overseas, enough to make him secure for life.
These kind of sales don't bother me, there are lots of reasons to sell stocks- divorce,illness, etc. If all the board was selling large amounts in a concentrated time span I would probably worry some.
It should be noted that some companies chose the BOD to be as ignorant of the business and as dumb as possible so the CEO and a few others can more easily loot the company but there is no evidence of that here.
Any tech company (and many non tech companies) run the risk of becoming obsolete very quickly and the CEO becomes redundant. Or he can lose his job via an insider revolt. Being a CEO is not the same as working for the Post Office . Even some of them have lost their jobs.
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