ORGANIC farmer Stephen Marsh has been handed an indefinite decertification by the National Association of Sustainable Agriculture Australia. [...] If the Marsh family proceeded with a lawsuit, it would become the first case in Australia to decide who is responsible for the substantial cost when a non-GM crop is contaminated by a GM one. A potential lawsuit would also set Mr Marsh up against Monsanto, which owns the Roundup Ready GM technology and was reported to have said it would back the GM grower in a court case.