Cochlear shares plunged 18.9 per cent to a more than three-year low of $199.22 on Friday after the company trimmed its guidance because its next-generation implant took longer to roll out than anticipated.
Cochlear's statutory net profit for the half-year to December 31 was down 21 per cent to $161.5 million, as sales fell two per cent to $1.18 billion.
The company lost sales in 2025 after the launch of its Nucleus Nexa implant was delayed because of product registration and contract renewal issues.
As a result, Cochlear expects full-year profit to come in at the lower end of its August guidance of $435 million to $460 million.
Cochlear says its Nucleus Nexa is being sold in most markets and receiving a positive reception from professionals and recipients.
The company says the Nexa sound processor is the world's lightest and smallest, while the implant is the only one to feature upgradeable firmware, giving recipients future-proof access to new technology.
"Overall, we saw a very successful launch, which sets us up for the future," chief executive and president Dig Howitt told analysts on Friday.
Cochlear had generally been able to negotiate increased prices for the new system with hospitals, Mr Howitt said.
Cochlear said it would pay an interim dividend of $2.15 per share, the same payout as a year ago.
The dividend will be 85 per cent franked, up from 80 per cent a year ago.
RBC Capital Markets analyst Craig Wong-Pan said the result was weaker than consensus expectations and RBC's forecasts.
"We expect the stock to be weaker today given the soft 1H performance and management lowering full-year expectations," Mr Wong-Pan wrote before the sharp sell-off.
Companies to be whipsawed during the February 2026 earnings season include blue-chip CSL, whose shares on Friday were down 15.6 per cent since the start of the week.
Others include wealth manager AMP and furniture e-retailer Temple & Webster, whose shares on Thursday sold off by more than a quarter and almost a third respectively.
On the flip side, ANZ and Commonwealth Bank posted strong gains when reporting their earnings, with CBA on Wednesday climbing 6.8 per cent - its best gains since March 2020 - and ANZ soaring 8.5 per cent on Thursday.
Andrew Dale, a partner at Sydney-based ECP Asset Management, said the previous week had also been volatile.
He said part of this had been driven by overseas markets, where there were questions over how artificial intelligence technology could affect the business models of expensive software-as-a-service stocks.
But Mr Dale said sharp movements in shares were becoming more pronounced during reporting season, the periods in February and August when most companies announce their profit or losses.
"It has become somewhat of a common trend that reporting season is a period of high volatility," he said.
"This shouldn't be a surprise to investors, and should be expected going forward."
