The S&P/ASX 200 Index (ASX: XJO) is having a subdued finish to the week. At the time of writing, the benchmark index is down slightly to 8,324.3 points.

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

4DS Memory Ltd (ASX: 4DS)

The 4DS Memory share price is down 7% to 3.8 cents. This semiconductor company's shares are falling today after it raised capital. 4DS Memory advised that it has received binding commitments from institutional and high net worth investors for a placement of shares to raise $6 million. These funds will be raised a 3.6 cents per new share, which represents a 12.2% discount to its last close price. However, it also represents a 55% discount to where it shares were trading when the previous capital raising was abandoned last month. The proceeds will be used to progress the design agreement with Infineon Technologies.

Lynas Rare Earths Ltd (ASX: LYC)

The Lynas Rare Earths share price is down over 5% to $6.71. This follows the release of the rare earths producer's quarterly update. Lynas reported an uplift in sales revenue to $141.2 million and sales receipts to $145.9 million for the quarter. This was despite continuing low market prices and subdued inside China demand. While positive on paper, this appears to have fallen short of the market's expectations for the three months.

Rea Group Ltd (ASX: REA)

The Rea Group share price is down over 2% to $230.88. This morning, analysts at Morgans held firm with their hold rating and $215.00 price target on this property listings company's shares. While the broker is positive on the company, it isn't a fan of its valuation. As a result, Morgans thinks that investors should wait for a more attractive entry point before picking up shares.

Rio Tinto Ltd (ASX: RIO)

The Rio Tinto share price is down over 1% to $118.24. This follows a lukewarm response to the miner's quarterly update from brokers this morning. Macquarie felt the update was mixed and highlights that Rio Tinto's iron ore production has had a soft start to 2025. In light of this, the broker has reaffirmed its neutral rating and $120.00 price target. It thinks BHP Group Ltd (ASX: BHP) shares would be a better option. In other news, there are rumours that Rio Tinto could be plotting a merger with fellow mining heavyweight Glencore (LSE: GLEN).