A group of Robert Mondavi shareholders, known as Bamboo Partners, has filed a lawsuit in California over the company's refusal to accept the $1.3 billion takeover offer from Constellation Brands. The offer, filed last week, was for the entire Robert Mondavi Group, and not just the luxury' brands that Mondavi has indicated it is willing to sell. The offer includes $333 million of assumed debt and is dependant on the company staying whole. A Mondavi spokeswoman said that it would consider all options that could potentially enhance shareholder value', but the plan to split the company is still going ahead, with shareholder approval set to be sought at the AGM on 30 November.