Pantoro's (ASX:PNR) substantial shareholder, Robmar Investments Pty Limited, continues to lift its stake in the company through on-market purchases.
Robmar now holds 18.2%, up from 16.4%, as outlined in notice in change of interests of a substantial holder.
The registered holder of the securities is Bell Potter Nominees.
Pantoro delivered record production of 9,598 gold ounces during the December 2016 quarter, a 30% increases on quarter on quarter.
All-in-sustaining-costs (AISC) for the quarter was A$1179 an ounce, and with increased production in the month of December, C1 reduced to A$759 an ounce and AISC to A$988 an ounce.
Gold is produced from the Halls Creek Gold Project in the Kimberly Region of Western Australia.
Pantoro's shares last traded at $0.23, a 12-month high, and three times higher than their value in February 2016.