Earlier quoted context omitted.
How does that level of transparency for a public company not lead to insider trading?
They can put in place some things to mitigate/prevent this. One example that comes to my mind is the use of trading windows for employees. I.e: you can buy company stocks only during some specific time windows announced at the start of the fiscal year.
But when you have access to info that could conceivably impact the stock price if revealed, you cannot do any trading even during those trading windows. That's why the top execs can typically (always, I think) only trade via pre-planned schedules.
I've been placed on the insider list in public companies when involved in secret projects (future acquisitions, typically) and that means zero trading for the duration of the project regardless of when employee trading windows open or close.