They argue that because family foundation make up a large proportion of total foundations, it is essential to have a better clarity of the definition. The Council on Foundations defines a family foundation as a "foundation whose funds are derived from members of a single family. At least one family member must continue to serve as an officer or board member of the foundation, they or their relatives play a significant role in governing and/or managing the foundation throughout its life. Most family foundations are run by family members who serve as trustees or directors on a voluntary basis, receiving no compensation; in many cases, second- and third-generation descendants of the original donors manage the foundation." The Rockefeller Foundation, and the Gates Foundation are two of the most renowned and influential family foundations in the United States. Private operating foundations are private foundations that use the bulk of their income to provide charitable services or to run charitable programs of their own. They make few, if any, grants to outside organizations. Thus, a private operating foundation sponsors and manages its own programs. A typical example of this would be a day camp for underprivileged children. Rather than providing grants to another organization to administer such a camp, which a standard private foundation would do, the private operating foundation will "operate" the camp. The private operating foundation will maintain a qualified staff as well as other personnel needed to carry out the program on a continuing basis. To qualify as a private operating foundation, specific rules, in addition to the applicable rules for private foundations, must be followed. A private foundation qualifies as a private operating foundation by satisfying two numerical tests. These tests ensure that the private operating foundation is conducting its exempt activities directly and not simply making grants to other organizations. The first of the two tests is an income test, which requires a specific amount of income to be spent on direct charitable activities. The second test is actually made up of three different tests: an asset test, an endowment test and a support test. However, the private operating foundation only has to satisfy one of these three tests, in addition to the income test, to qualify. Similar to the income test, these other three tests help to ensure that the private operating foundation is using its funds to meet the requirement of conducting direct charitable activities. In contrast, a private foundation that principally provides grants to other entities or to individuals for charitable or other exempt purposes would not qualify as an operating foundation, and instead would be called a "nonoperating foundation". The Carnegie Endowment for International Peace and the Getty Trust are examples of operating foundations. A corporate (company-sponsored) foundation is "a private foundation that derives its grant-making funds primarily from the contributions of a profit-making business.