The High Court in Wellington has reserved its decision in the latest appeal by GE Free New Zealand over an Environmental Risk Management Authority decision.
GE Free is challenging ERMA's decision to allow AgResearch to broaden its genetically modified animal research.
In April, ERMA approved a 20-year proposal for the Crown research institute to continue an on-going research programme with genetically modified cattle, as well as sheep and goats, to produce therapeutic proteins in milk.
GE Free says that by granting such a broad brush application, ERMA had not given the public the ability to comment on the individual risks of each new organism that AgResearch intends to develop.
The court case is part of a legal saga: GE Free has been fighting to stop applications for genetic modification on animals in New Zealand.
Earlier this year it lost an appeal in the Supreme Court over four applications that AgResearch made to ERMA to develop biopharmaceuticals and nutraceutical products from 18 species of genetically modified animals.
The Supreme Court ruled that an application to create genetically modified organisms cannot be challenged at such an early stage, except in the rarest of cases.