SEC staff has been instructed to seek subpoenas for devices such as computer hard drives and cell phones only rarely.
In many cases, there could be unintended consequences, such as exposing authorities to other sensitive materials on a device outside the scope of the investigation. The SEC claims to be sensitive to this situation. Typically, the SEC staff returns potentially privileged documents back to defense counsel. Other times, search terms are agreed on ahead of time to protect privileged documents.
In sum, those under the SEC light need to be cautious about turning over these devices to the government.