Were they abnormally liquidating those things at the end of 2021 compared to other years?

Asking because I would expect executives to sell "by the 10s of millions" pretty much every year. Especially since they cannot really sell on a whim (in the US), as executives are legally required to file their stock purchase/sell plans with SEC far ahead of time.

10b5-1 plans do not have to be filed with the SEC.

(The use of a 10b5-1 is also not technically a legal requirement, but is a workaround to allow planned sales even if you become aware of material, non-public information between the time of entering into the plan and the time of the trade.)

You can prove the boss had an intention to sell his stock based on a feeling of future doom (or just greed). What’s tougher to prove is whether he delayed an announcement by a week so one more sale went through before the stock took a hit.

Or speeding up good news so his scheduled sale rides the high.

the best thing about them is you can constantly schedule large stock sales, and just cancel the ones that don't favour you.

Look ma, no inside information.