The Michael Fay-led consortium has asked the Court of Appeal to review one aspect of the High Court decision on the Shanghai Pengxin bid to buy the 16 Crafar farms.
The Overseas Investment Office was directed by the High Court to reconsider the application by the China-based consortium, on the basis the economic benefit test had not been applied correctly.
Crafar Farms Purchase Group spokesperson Alan McDonald says the group, which includes farmers and iwi, also believes another requirement in the law has not been met.
Shanghai Pengxin has criticised the group, saying it has conducted a self-serving campaign of half truths and allegations.
It also says the group would not be bound to keep to the conditions of the sale, as would a foreign purchaser.
But Mr McDonald says it has always been upfront about its bid and its reasons for wanting to buy the farms.
He says the group would also be happy to be open to ongoing scrutiny about requirements for riparian planting, local pa sites and walking access.
Shanghai Pengxin has offered $200 million for the farms.