1987 Constitution of the Philippines
Section 13. The President, Vice-President, the Members of the Cabinet, and their deputies or assistants shall not, unless otherwise provided in this Constitution, hold any other office or employment during their tenure. They shall not, during said tenure, directly or indirectly, practice any other profession, participate in any business, or be financially interested in any contract with, or in any franchise, or special privilege granted by the Government or any subdivision, agency, or instrumentality thereof, including government-owned or controlled corporations or their subsidiaries. They shall strictly avoid conflict of interest in the conduct of their office.
The spouse and relatives by consanguinity or affinity within the fourth civil degree of the President shall not, during his tenure, be appointed as Members of the Constitutional Commissions, or the Office of the Ombudsman, or as Secretaries, Undersecretaries, chairmen or heads of bureaus or offices, including government-owned or controlled corporations and their subsidiaries.