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 0.6% to 7,819.2 points.

Four ASX shares that have failed to follow the market higher today are listed below. Here's why they are dropping:

The ALS share price is down over 6% to $12.85. This morning, the testing services company announced an agreement to acquire the remaining 51% interest in Nuvisan for zero cost. It is a European-based contract research organisation with two distinct and separable entities, Nuvisan GmbH focused on pre-clinical and clinical development services, and ICB focused on drug discovery services. It generated revenues of ~A$245 million in calendar year 2023. In other news, ALQ updated its guidance for FY 2024 underlying net profit after tax to be at the lower end of its prior guidance of $310 million to $325 million.

The EOS share price is down 18% to $1.70. This follows the completion of the space and defence systems company's institutional placement. It raised $35 million from investors at a discount of $1.70 per new share. The company will now push ahead with a $5 million share purchase plan at the same price. These funds will be used to support future sales growth in key global markets.

The NRW Holdings share price is down 3% to $2.84. This has been driven by the diversified contract services provider's shares going ex-dividend this morning for its upcoming dividend. Eligible shareholders can look forward to receiving its 6.5 cents per share fully franked dividend next month on 11 April.

The Patriot Battery Metals share price is down 3% to 88.5 cents. This is despite the lithium explorer announcing the discovery of a new spodumene pegmatite occurrence at the Corvette project in Canada. Management commented: "The discovery highlights the extensive nature of the spodumene mineralized system along the CV Lithium Trend, which extends across the Property where a large portion remains unexplored for lithium pegmatite."