The S&P/ASX 200 Index (ASX: XJO) is having a poor finish to the week. In afternoon trade, the benchmark index is down 0.5% to 8,751.3 points.
Four ASX shares that are falling more than most today are listed below. Here's why they are tumbling:

Image source: Getty Images
Brainchip Holdings Ltd (ASX: BRN)
The Brainchip share price is down 3% to 15 cents. This follows the release of another disappointing update from the struggling semiconductor company. For the three months ended 31 March, Brainchip recorded customer cash inflows of US$700,000. However, this couldn't stop the company from recording an operating cash outflow of US$5.3 million for the three months. This led to its cash balance reducing to US$25.3 million from US$31.7 million.
Fortescue Ltd (ASX: FMG)
The Fortescue share price is down 5% to $19.93. For the third quarter of FY 2026, Fortescue reported total iron ore shipments of 48.4 million tonnes (Mt). This was below consensus estimates of approximately 49Mt, which may have disappointed investors. Fortescue Metals and Operations CEO, Dino Otranto, was pleased with the quarter. He said: "We delivered a solid quarter, contributing to record shipments of 148.7 million tonnes for the nine months to March. That reflects a significant effort from the team right across the business." Fortescue also separately announced that it has approved a US$680 million investment to expand its green energy capacity in the Pilbara.
IGO Ltd (ASX: IGO)
The IGO share price is down 15% to $7.28. This battery materials company's shares have been sold off following the release of its quarterly update. Although it posted a 45% increase in group sales revenue to $119.7 million, the market appears disappointed with an update on its guidance. IGO has updated full-year guidance for Greenbushes spodumene production to 1,375kt to 1,425kt (down from 1,500kt to 1,650kt). IGO's CEO, Ivan van Vella, said: "Fundamental changes to operating approaches and systems take time to be effective and improvements are typically not linear. Greenbushes is a world-class asset and generated 75% EBITDA margin this quarter. I am confident the work underway will deliver the required performance and overall value optimisation."
Life360 Inc (ASX: 360)
The Life360 share price is down 4% to $20.89. This follows another selloff of software stocks on Wall Street overnight. The catalyst for this may have been the release of GPT-5.5 by ChatGPT owner OpenAI. It stated: "We're releasing GPT‑5.5, our smartest and most intuitive to use model yet, and the next step toward a new way of getting work done on a computer."