What you should always ask, immediately after reading "insiders have sold $X of shares" is "out of how much, total?". Also, like a sibling comment points out,

What you should always ask, immediately after reading "insiders have sold $X of shares" is "out of how much, total?". Also, like a sibling comment points out, may of these people have predetermined plans to exercise and sell, and may have tax reasons for selling 30% of stock awards (https://www.investopedia.com/terms/r/rule-10b5-1.asp https://www.investopedia.com/terms/r/rule-10b5-1.asp).