25 CFR §900.235

The standards must prohibit an officer, employee, or agent (including a subcontractor) from participating in the review, analysis, or inspection of trust transactions involving an entity in which such persons have a direct financial interest or an employment relationship. It must also prohibit such officers, employees, or agents from accepting any gratuity, favor, or anything of more than nominal value, from a party (other than the Indian tribe) with an interest in the trust transactions under review. Such standards must also provide for sanctions or remedies for violation of the standards.