James Hardie Industries (ASX:JHX) is being investigated by law firm Maurice Blackburn over potential disclosure failures ahead of the release of its fiscal first-quarter 2026 results, which precipitated a 34% decline in its Australia-listed shares over two trading days in August 2025, the law firm said.

Maurice Blackburn said the company in May 2025 guided for fiscal 2026 organic sales and earnings before interest, taxes, depreciation, and amortization growth across all regions, but in August 2025 reported weaker-than-expected quarterly results that included a fall in earnings and net sales.

"Our investigation concerns whether James Hardie engaged in misleading or deceptive conduct and/or breached its continuous disclosure obligations by failing to disclose material issues affecting its North American Fiber Cement segment," Maurice Blackburn said.

James Hardie Industries did not immediately respond to a request for comment from MT Newswires.

The company's shares were gaining more than 1% in recent Tuesday trade.