How do they prove this? A lot of people play earnings. Amazon is not an obscure stock. In fact, making an earnings play on Amazon is probably one of the more reasonable safer things to do compared to what the world is up to now days.
I think they also have separate flags on insider's tax returns to look for any unusual capital gains from market transactions. It's not a trivial problem to make trades in an account completely unrelated to you and then get the illegit proceeds back into your control without tripping some flags.
Also, most of the volume in these stocks are huge algorithmic trades from institutional investors and funds. They also tend to move in herds based on when analysts release new reports or change ratings on the stock. Thus, those are pretty easy to filter out of a search. Unusual trades from individual brokerage accounts are going to stand-out. Especially if those accounts aren't making similar trades in other stocks.
When they get suspicious matches they run them down to see if there's anything there. I used to be an insider at a big tech company and there's quite a bit of scrutiny. You'd have to be really stupid to do that shit. Especially repeatedly with large amounts.
> When they [the SEC] get suspicious matches they run them down to see if there's anything there
Sounds like how casinos ban card-counters.
Also, by the way, they were legally not allowed to trade during those times at all, due to her specific job and the blackout period that cme with.
If he had just stuck with stocks, I'm sure it would've been harder to prove. But with options and dates, timing of it... it's hard to get away.
Also, had he done this once or twice, they might not have found it but 11 quarters in a row is going to get noticed eventually.
Edit: blah, nevermind: https://techcrunch.com/2019/10/24/after-its-first-earnings-m...
I guess if he dodged those earnings plays, that would build a good case.
edit: Blackouts include the employee and all family members. You can not trade during blackout periods.