They claim that in 2008 TPI failed to make timely disclosure to investors of material information regarding its earnings and forecasts and that shareholders subsequently suffered big losses when TPI's share price fell.

Investors could seek damages from TPI relating to alleged misleading or deceptive conduct and breaches of the TPI's continuous disclosure obligations.

Maurice Blackburn's New South Wales principal, Ben Slade, said Australian-listed companies were required to make timely disclosure to the market of information that could materially affect their share price.

"We believe that TPI has failed in its responsibility to provide this information to the market," said Slade; adding that some large institutional and professional investors, who had requested that they not be identified, had already expressed an interest in a class action.

He said that between 2005 and 2008, TPI grew exponentially via acquisitions and mergers and had said it would deliver sustainable and increased future earnings and profit.

In February 2008, TPI confirmed previous forecasts for the 2008 financial year of earnings before interest, tax, depreciation and amortization (EBITDA) of $545-$560 million, and net profit of $175-$180 million. In August 2008, TPI delivered results that largely achieved the forecasts.

In August to November 2008, TPI forecast double-digit EBITDA growth for the 2009 financial year. At TPI's annual general meeting in November 2008, TPI confirmed previous forecasts.

TPI also stated that the business was near recession-proof, that there was no need to raise capital, and that impairment of acquired assets would be unlikely.

But, on February 16, 2009, TPI announced that its 2009 performance was expected to be adversely affected by weaker commodity prices and foreign exchange rates.

In the first half of the financial year, it would write down the value of its investments in listed securities by $46 million. TPI was also reviewing its capital structure, and the company was in talks with potential cornerstone investors.

Slade said that by the close of trade on the Australian Securities Exchange on February 16 last year, more than $300 million had been wiped from TPI's value after its share price plunged from $2.90 to $1.80.

TPI shares were up 1.5c at $1.395 Monday.