Aderans Co. shareholders narrowly approved a takeover defense Thursday put forth by the wig maker's management, overriding opposition from top shareholder Steel Partners, the U.S. hedge fund, company officials said.

The measure was passed at Aderans' general shareholders' meeting, where 54.71 percent of shareholders backed the company's "advance warning system" proposal.

Steel Partners had tried to collect enough proxies from other shareholders to vote down the proposal, saying it would not protect the rights or interests of shareholders but just management alone.