Shares of Cisco fell 2.8% in New York, and Splunk surged 21%.
Cisco Systems Inc. agreed to buy Splunk Inc. in a deal valued at about US$28 billion, representing its biggest acquisition yet and a massive push into software and artificial intelligence-powered data analysis.
Cisco will pay US$157 a share in cash, the companies said in a statement Thursday, or a 31% premium to Splunk’s previous closing price on Wednesday. The deal value represents roughly 10% of Cisco’s market value.

