In afternoon trade, the S&P/ASX 200 Index (ASX: XJO) is on course to record a decent gain. At the time of writing, the benchmark index is up 0.5% to 8,231.6 points.

Four ASX shares that are rising more than most today are listed below. Here's why they are climbing:

ARB Corporation Ltd (ASX: ARB)

The ARB share price is up over 3% to $45.03. This follows the release of an update on its proposed acquisition of the 4 Wheel Parts business from Hoonigan. ARB notes that the agreement was subject to court approval in conjunction with Hoonigan's court-supervised reorganisation in the United States following its bankruptcy. This morning, it revealed that the court did not receive any competing offers for the 4 Wheel Parts business. As a result, ARB is expecting the court to approve the agreement at a hearing next week.

Arcadium Lithium (ASX: LTM)

The Arcadium Lithium share price is up a further 39% to $8.21. This has been driven by the announcement of a takeover agreement with Rio Tinto Ltd (ASX: RIO). According to the release, Rio Tinto will acquire the lithium miner through an all-cash transaction for US$5.85 per share (A$8.71 per share). This values Arcadium Lithium at approximately US$6.7 billion (A$10 billion). Rio Tinto's CEO, Jakob Stausholm, said: "Acquiring Arcadium Lithium is a significant step forward in Rio Tinto's long-term strategy, creating a world-class lithium business alongside our leading aluminium and copper operations to supply materials needed for the energy transition."

Netwealth Group Ltd (ASX: NWL)

The Netwealth share price is up 4% to $27.19. This follows the release of the investment platform provider's quarterly update this morning. Netwealth revealed that its funds under administration (FUA) was $95.4 billion at the end of September. This was up by $7.4 billion from the prior quarter, driven by FUA net inflows of $4 billion and positive market movement of $3.4 billion.

Regis Resources Ltd (ASX: RRL)

The Regis Resources share price is up 2.5% to $2.04. Investors have been buying this gold miner's shares following the release of its first quarter update. Regis Resources revealed that total group production for the first quarter of FY 2025 came in at 94,500 ounces. This means that the company is on track to achieve its full year production guidance of 350,000 ounces to 380,000 ounces. Management also advised that it generated $85 million in cash during the three months, boosting its cash and bullion balance to $380 million.