The Wellington court listened on Monday and Tuesday before reserving its decision, a Shell NZ spokesperson told PetroleumNews.net but declined to comment further.

Shell – in what may be its last attempt to win Maui operatorship – appealed to New Zealand’s highest court last July after the High Court had stymied its takeover plans by ruling that current Maui operator Shell Todd Oil Services (STOS) was operator for the life of the field.

Shell had wanted to use its casting vote on the STOS board to force STOS – equally owned by Todd and Shell – to resign as Maui operator so it could take over.

During the high court case, Shell NZ disagreed with that court’s interpretation of the core terms of the 2002 heads of agreement (HOA) between Shell and Todd.

The 2002 HOA had updated the original Shell-BP-Todd joint venture agreement that specified all New Zealand exploration and production would be done through an unincorporated organisation owned by the parties but holding no equity in any licences – originally Shell BP Todd Oil Services, then STOS after BP quit New Zealand over 15 years ago.

Shell has already won a similar court case, which Todd also opposed, enabling it to last year remove STOS as Pohokura operator and take control of that near-shore gas field.

Documents produced during that high court squabble revealed Shell feared a $US100 million ($A120 million) loss in the value of its New Zealand oil and gas assets if it did not take the operator’s role at its major Taranaki fields, and that it wanted to re-organise its New Zealand operations in preparation for a possible sale.