The IRS says this:
"any transaction between an organization and a private individual in which the individual appears to receive a disproportionate share of the benefits of the exchange relative to the charity served presents an inurement issue. Such transactions may include assignments of income, compensation arrangements, sales or exchanges of property, commissions, rental arrangements, gifts with retained interests, and contracts to provide goods or services to the organization.”
Many Americans believe that the Clintons Foundation has directly or indirectly unduly benefited an individual or other person(s) that have a close relationship with the organization or are able to exercise significant control over the organization.