CSL Ltd (ASX: CSL) shares are shaking off the broader market selling action today to push higher.

Shares in the S&P/ASX 200 Index (ASX: XJO) biotech stock closed yesterday trading for $245.21. In afternoon trade on Thursday, shares are changing hands for $246.51 apiece, up 0.5%.

For some context, the ASX 200 is down 0.5% at this same time.

Despite today's welcome lift, CSL shares remain down 12.3% in 2025.

So, is the Aussie biotech giant now trading for a bargain, or does the stock have further to fall?

For some greater insight into that multi-million-dollar question, we defer to Crispin Murray, head of Australian equities at Pendal.

Can CSL shares return to outperform?

On 14 December 2021, CSL announced its intention to acquire Vifor Pharma, an iron deficiency and nephrology treatment company, for US$11.7 billion. That acquisition was completed on 9 August 2022.

But a lot of investors, including Murray, were critical of the cost of that acquisition. And many reacted by hitting their sell buttons.

Indeed, CSL stock remains down around 17% since 10 December 2021, just prior to the Vifor acquisition announcement.

"Their return on capital collapsed. And clearly they overpaid for an average business," Murray said (quoted by The Australian Financial Review).

However, Murray believes the future is looking brighter for CSL shares.

"Our bet is the sort of failures of the last five years have finally permeated into the psyche of the company. They realise they need to improve," he said.

According to Murray:

This remains an incredibly good business. Patients rely on their products and their long-term requirement for those products.

The fund manager forecasts that management will be more cost-conscious moving ahead. And he also said he expects CSL to engage in a share buyback within the "next few months".

"We think the market will flip in terms of looking at that as a return to its better growth days," he said.

As for the potential impact of United States President Donald Trump's threatened tariffs on pharmaceuticals, Murray added:

We think there's a downside of maybe 10% to 15%… but that's assuming the company doesn't respond. Companies can realign where they produce things. They can do that within two or three years.

What's the latest from the ASX 200 biotech stock?

The last price-sensitive news to directly impact CSL shares was the company's half-year results release on 11 February.

Highlights included a 5% year-on-year increase in revenue in constant currency to US$8.48 billion. And net profit after tax (NPAT) for the six months was up 7% in constant currency to US$2.04 billion.

This led management to boost the interim dividend by 15% to AU$2.07 per CSL share.