The Boston University trustees voted yesterday to sell $6.6 million of B.U.'s portfolio investments that do not permit it to vote as a shareholder and influence corporate policy in South Africa.

Baily Mason, Chairman of the B.U. trustees' Investment Advisory Committee and special assistant to the president, said last night the trustees decided to "phase-out" their non-voting bank deposits and bonds because these holdings "do not offer the university sufficient leverage on corporate practices."

Won't Sell Common Stock

The trustees, however, voted no to sell $6 million in common stock in companies active in South Africa, a demand of the South African Support Committee, a B.U. student group. B.U. has a total portfolio worth approximately $78 million.

Mason said the university will allow the investments to expire and will most likely invest in U.S. Treasury bills or in banks that are not active internationally.

'A Half-Step'

Matthew Davis, a member of the South African Support Committee, said last night the trustees' decision is "a half-step toward divestiture."

Davis said the trustees should divest of their common stock in corporations active in South Africa because their sale of the bank deposits indicates they "agree with the philosophy of divestiture."

Hugh Calkins '45, chairman of the Harvard Corporation Committee on Shareholder Responsibility, declined to comment on the B.U. trustees' decision last night.

The Harvard Corporation said in a statement issued last April that it would not hold non-voting investments in banks that make loans to the South African government but stated it would retain its common stock and influence corporate practices in South Africa as a shareholder. J.L.T.