A company's code of ethics is more than a set of lofty principles. It spells out what employees may or may not do. The Securities and Exchange Commission can levy penalties against the company's officers if the code isn't enforced or isn't well-designed. Employee trading is another matter. At Charles Schwab, the nation's largest discount brokerage, and at broker Jack White, employees' trades are segregated in a special division.
Employees have to call that division to make trades.
We did that many years ago so compliance officers could get a handle on monitoring employee trades. All employee trades have to be approved by Schwab's compliance department. Fidelity says it's in the process of restricting access to employee accounts, but declined to be more specific. And it says it will deal with any violations of its policies harshly. Mutual fund accounts are more heavily guarded than brokerage accounts, probably because there is less urgency involved with buying and selling fund shares.