A well-placed legal source said the appeal opened the door for a cross appeal from Shanghai Pengxin or even the Crown to be heard at the same time.
The Fay group later said there was always a chance Justice Miller's decision would be appealed against by Shanghai Pengxin or the Crown and they believed that risk had increased.
However the appeal is likely to delay the OIO's reconsideration of Shanghai Pengxin's offer, something it has previously said would take "a matter of days".
Shanghai Pengxin spokesman Cedric Allan said the company was still considering the implications of the Fay group's latest move and would make a statement today.
He said the group's criticism of the Chinese company's farming credentials were part of "a self-serving campaign of allegations and half-truths".
The company had a controlling interest in a profitable cropping farm in Bolivia, half as big again as all the Crafar farms, and had also been involved in cropping and sheep farming in China for years, with a target of three million sheep within five years.
Mr Allan said the Fay group's offer was a "phantom bid" which had already been rejected by the receiver.