"We think the court...erred in determining that these non-human mammals could be considered a 'composition of matter' within the terms of the Patent Act," said Rick Woyiwada, the government laywer on the case. "Similarly, we think they erred in determining that the non-human mammals can be considered an invention."

Legal experts say that the decision will depend largely on whether the court focuses on the meaning of the patent code or whether it takes a more philosophical perspective in its analysis.

"If they use a legalistic framework, they'll uphold the Court of Appeals," Somerville said. "But it's almost certain that the court will do a broader-based social and symbolic analysis as well as a technical legal analysis."

However, it is hard to predict what the Supreme Court will decide if it chooses to review the case because it has considered so few biotechnology matters.

"The court hasn't dealt much with biotechnology, and the highest case that got there on patenting life forms had to do with selective breeding, not genetic biotech intervention," said Michelle Swenarchuk, director of international programs at the Canadian Environmental Law Association, which lobbied the government to appeal.

In general, the court is known for its conservatism.

"In almost any field of law they are not inclined to break out and start smashing paradigms," said David Beatty, a University of Toronto law professor. "It's cautious in most areas of its work. If this case is going to ask it to do anything beyond the norm, [the court] will be a chameleon."