The University may withdraw and expend its endowment fund income to defray any expenses necessary to its operation, including expenses of operations and maintenance, administration, academic and support personnel, construction and renovation, community and student services programs, technical assistance, and research. No endowment fund income or corpus may be used for any type of support of the executive officers of the University or for any commercial enterprise or endeavor entered into after January 1, 1981. Except as provided in subsection (b), the University shall not, in the aggregate, withdraw or expend more than 50 per centum of the total aggregate endowment fund income earned prior to the time of withdrawal or expenditure.
20 U.S. Code § 130aa–3 - Withdrawals and expenditures
(a) Defrayment of expenses; restrictions on use of income or corpus; limits on withdrawals or expenditures
(b) Authority of Secretary; withdrawal or expenditure beyond limits; circumstances demonstrating necessityThe Secretary is authorized to permit the University to withdraw or expend more than 50 per centum of its total aggregate endowment income whenever the University demonstrates such withdrawal or expenditure is necessary because of—
(c) Repayment of Federal share of amounts improperly expended or withdrawn; endowment fund corpus; income
The University shall not withdraw or expend any endowment fund corpus. If the University withdraws or expends any endowment fund corpus, the University shall repay the Secretary an amount equal to 50 per centum of the amount withdrawn or expended (representing the Federal share thereof) plus any income earned thereon.