Treasury Wine Estates has been hammered on the stock market, with its shares falling by 20 per cent after it issued a profit downgrade due to weaker sales in Australia and China.
The company behind Penfolds and Wolf Blass has cut its full year earnings forecast from between $230 million and $250 million to between $190 million and $210 million.
It expects first half earnings, which will be announced in February, to be between $41 million and $46 million, down from $73 million last year.
Treasury Wine shares fell to $3.64, their weakest price in almost two years, wiping $589 million from the value of the company.
Weaker than expected sales in Australia, following the company's decision to lift prices on some products and focus less on Christmas promotions, had contributed to the profit downgrade, it said.
A decline in Chinese demand for premium wine had also hit sales volumes.
Treasury Wine also said it had continued to reduce shipments to the US while increasing investment across the group, especially in Asia.
The profit downgrade is the latest in a string of bad news for Treasury Wine, which last year poured more than $35 million worth of excess or aged commercial stock down the drain in the US.
The controversial move, which was part of a broader $160 million writedown, ultimately led to the departure of chief executive David Dearie.
Law Firm Maurice Blackburn and litigation funder IMF last October announced funding of a class action against Treasury Wine, alleging the company misled the market and breached its continuous disclosure obligations in its communication of the financial impact of over-stocked US distributors to investors.
On Thursday, Maurice Blackburn managing principal Ben Slade said the latest profit downgrade raised "questions of transparency" about the company's operations.
"TWE's announcement this morning suggests that continuous disclosure requirements may not have been complied with," he said in a statement.
"We are confident that the company's shock $190 million downgrade announcement in July last year was indicative of such a breach. It may have happened again."