Insider attacks are almost impossible to guard against. There is no standard way to prevent them, other than by constant vigilance.
And, very often, it's the guards and watchers who know enough to do the attacking.
So it's not really that surprising that the guy who has been caught doing insider trading on Apple stock is Apple's Senior Director of Corporate Law and Corporate Secretary the head of the company's corporate law group, and responsible for ensuring compliance with Apple's insider trading policy, as well as determining the criteria for those restricted from trading around quarterly earnings announcements.
The Securities and Exchange Commission notes that it was definitely Gene Levoff at fault, and not Apple. "Apple had an insider trading policy that applied to all employees. Many employees, including Levoff, also received notice when restricted trading periods, known as 'blackout' periods, were in effect. The notices, emailed to employees subject to the blackout periods, reminded them of the insider trading policy, and since at least 2015, included a link to the insider trading policy."
............ This message may or may not be governed by the terms of http://www.noticebored.com/html/cisspforumfaq.html#Friday or https://blogs.securiteam.com/index.php/archives/1468
Well, if everyone completes the Business Conduct Guidelines (BCGs) once per year, and this is recorded, then there is no way out - obviously made a error of judgement and hoped that he would not be caught.
It will all come out in the wash.
However, perhaps he hoped that the monitoring systems, were not so good.