The S&P/ASX 200 Index (ASX: XJO) has been bouncing around today and has just slipped into the red. At the time of writing, the benchmark index is down slightly to 8,544 points.

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

Betr Entertainment Ltd (ASX: BBT)

The Betr Entertainment share price is down 3.5% to 28 cents. This sports betting company's shares have been sold off this week after rival Pointsbet Holdings Ltd (ASX: PBH) rejected its takeover offer and pushed ahead with one from MIXI Australia. Betr continues to believe that its offer is superior. This morning, it stated: "The betr Board, which has an unparallelled track record in delivering shareholder value through successfully-integrated acquisitions, strongly believes that the betr Proposal remains clearly superior to the MIXI Proposal. The betr Proposal will deliver $1.33 in value to PointsBet shareholders who elect and receive consideration in line with the funding mix – compared to the $1.20 offered by MIXI."

Regis Resources Ltd (ASX: RRL)

The Regis Resources share price is down 2.5% to $4.76. The catalyst for this appears to have been a broker note out of UBS this morning. According to the note, the broker has downgraded the gold miner's shares to a sell rating (from neutral) with a $4.75 price target. While the broker believes that Regis Resources will achieve the upper end of its guidance range this year, it isn't enough to maintain a more positive rating. Its analysts feel that its shares are fully valued following recent share price gains.

St Barbara Ltd (ASX: SBM)

The St Barbara share price is down 13% to 33 cents. This morning, St Barbara downgraded its FY 2025 gold production guidance to between 50,000 and 52,000 ounces. This follows heavy rainfall at the company's Simberi operations in Papua New Guinea. Management revealed that more than 100mm of rain fell during June, including 60mm in just three days. St Barbara's CEO, Andrew Strelein, stated: "This rainfall event has disrupted access to higher grade feed from Pigibo Central at a critical time for achievement of guidance. The missed benches are however anticipated to be mined in July."

Woodside Energy Group Ltd (ASX: WDS)

The Woodside share price is down 1% to $25.70. This may have been driven by a combination of profit taking from some investors following a strong gain in recent sessions and a pullback in oil prices overnight. The latter reflects optimism that Israel and Iran will soon agree to a ceasefire.