The Tokyo District Court on Thursday turned down Nireco Corp.'s petition to revoke an injunction against the firm implementing what was to be Japan's first poison pill measure.

The latest ruling confirmed the June 1 court order issued in response to an injunction request filed by SFP Value Realization Master Fund Ltd., a Cayman Islands-based investment fund and Nireco shareholder, to prevent the Tokyo-based control- and measuring-equipment maker from issuing free stock subscription warrants to all shareholders in the event of an unwelcome takeover bid.

The firm had planned to issue warrants to shareholders of record as of March 31 so they could buy up to two Nireco shares at 1 yen each for every share owned. If all the shareholders exercised the warrants, the number of outstanding Nireco shares would triple, diluting the percentage of shares held by a firm attempting a takeover.