Yes, the law only stipulates that civil servants can't do business, but it doesn't stipulate that their immediate family members can't do business. However, it is not allowed to operate within the scope of a wife's authority and can only prevent internal information from leaking.

The relevant legal provision is Article 53 of the Civil Service Law. Civil servants must abide by discipline and must not commit any of the following acts:

(14) Engage in or participate in profit-making activities and hold concurrent positions in enterprises or other profit-making organizations;

(16) other acts that violate discipline.

This article doesn't just stipulate that civil servants can't register for business in their own names, but stipulates that civil servants can't participate in profit-making activities. Obviously, signing an economic contract must have participated in profit-making activities. Whether or not to participate in profit-making activities is also determined by the disciplinary department after investigation.