“Nokia is not preparing an offer for, Juniper Networks related to an acquisition of that company,” the company said in a statement.
CNBC had earlier reported, citing sources, that Nokia was in talks to buy Juniper at an offer that would value the company at around $16 billion.
Juniper had a market capitalization of around $11.26 billion as of Wednesday’s close, according to CNBC.
The Sunnyvale, California-based company’s shares had soared 18 percent to $35 in extended trading after the CNBC report.
Nokia has been building its telecom equipment business since selling its mobile phone unit to Microsoft Corp (MSFT.O).
It bought Alcatel-Lucent for about $17 billion last year to give it a larger fixed-line network business and make it less dependent on mobile broadband.
Juniper was not immediately available for comment.