system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How could a senior executive of a company sell any of that company's stock without it being insider trading?
gpt
There are two primary ways:

1) They have transactions arranged to sell at pre-determined times well in advance, for example they want to sell $250k worth of shares on the last day of every quarter.

2) There are "blackout" periods where insiders are advised that they are not able to trade. These are typically at the end of a fiscal quarter when executives become aware of financial performance, or ad hoc when there is a material event being discussed like an acquisition. The company's legal department will advise those "in the know" when they can/can't sell because the executive meets the criteria of having "material, non-public" information about the company.