Ann: Further Northern Extension to High Grade Mineralisation, page-113

This info has been in the public domain since this ann 1/5/18. It won't buy on-market, I agree there.

As part of the strategic relationship and subject to the waiver or satisfaction of any applicable listing rules of the ASX, Sandfire will hold an anti-dilution right that shall, subject to a number of conditions, enable it to maintain its interest at the Strategic Shareholding.
Sandfire shall also be entitled to nominate one director to the Board of the Company as a non-executive director should Sandfire’s relevant interest reach and be maintained in excess of 10%