Bull-Dog Sauce Co. on Wednesday became the first company in Japan to implement takeover defenses, issuing rights for new shares to block Steel Partners' takeover attempt.

Steel Partners Japan Strategic Fund (Offshore) L.P., which launched a tender offer for Bull-Dog shares in May, claims the sauce maker's poison pill contravenes shareholder equality.

The Tokyo High Court ruled the defense plan is legal and characterized the U.S. investment fund as a predatory acquirer trying to exploit the Japanese firm for a quick profit. Steel Partners has filed an appeal with the Supreme Court.