As reported Friday, law firms Maurice Blackburn and Slater & Gordon say they are close to filing respective shareholder class-action suits against Nufarm for misleading conduct and breaches of its continuous disclosure requirements.

An analyst at Credit Suisse, Rohan Gallagher, said Nufarm's operational headaches were its greatest concern, particularly after breaching a second banking covenant - its debt-to-earnings ratio - after revealing on Wednesday its net debt had blown out by 37 per cent. He said Nufarm was also suffering from structural changes in the worldwide glyphosate industry and growing competition domestically.

''They've got so many problems they've got to fix that [a class action] is the least of their worries at the moment,'' Mr Gallagher said.

Rubbing salt into the wound was confirmation yesterday that Nufarm has dropped out of the S&P/ASX 100 after heavy falls in its share price since halving its earnings guidance in July. Nufarm shares have plunged 70 per cent in the past year.

Nufarm spokesman Robert Reis yesterday said Nufarm had no comment on ''speculated legal action against the company''. He said the company was ''very happy'' with the progress of the talks with its bankers and was confident temporary waivers would be agreed on by mid-September.

While the talks had begun before Nufarm revealed it was in breach of a second covenant, Mr Reis confirmed discussions had canvassed the waiver of ''all relevant covenants''.

''So far as I understand, the banks would view that if a company breaches one covenant because of a lower earnings outcome, then it necessarily gets very close to other covenants,'' Mr Reis said. ''So the fact that another covenant might be breached I doubt is much of a surprise to the banks in these circumstances.''