Chipmaker Qualcomm has been told to refund BlackBerry US$814.9 million (A$1 billion) in an arbitration over royalties for certain past sales.
US-listed shares of BlackBerry were up 17.8 percent at US$9.07 in heavy trading, while they were also up 17 percent at C$12.03 in Toronto.
Qualcomm's shares were down about 2 percent at US$54.20.
The dispute started in 2016 following Qualcomm's agreement to cap certain royalties applied to payments made by BlackBerry under a licensing deal.
Qualcomm today said it does not agree with the decision of the arbitration panel, but the payment is binding and not appealable.
With BlackBerry planning to invest for growth in its software businesses, the arbitration award will strengthen the company's balance sheet and increase the likelihood of acquisitions, Canaccord Genuity analyst Michael Walkley wrote in a note.
He increased the price target to US$9.50 from US$8.
Qualcomm is also fighting a lawsuit filed by Apple, which has accused the company of overcharging for chips and refusing to pay some US$1 billion in promised rebates.
The US government has accused Qualcomm of resorting to anti-competitive tactics to maintain a monopoly over key semiconductors used in mobile phones.
BlackBerry today said a final award, which will include interest and reasonable attorneys' fees, will be issued after a hearing on May 30.
BlackBerry, which has a market valuation of about C$5.45 billion, reported revenue of C$1.31 billion in 2016, while Qualcomm, which has a market capitalisation of US$81.75 billion, reported a revenue of US$23.5 billion.