Key TakeawaysEuropean regulators gave their approval to networking equipment maker Cisco Systems Inc.'s $28 billion acquisition of cybersecurity company Splunk Inc.EU officials ruled Wednesday that the Cisco-Splunk transaction wouldn't raise competition concerns.Shares of Splunk soared after the $157-per-share deal was announced in September. Cisco Systems Inc. (CSCO) received European Union (EU) regulatory approval for the networking equipment maker’s $28 billion purchase of cybersecurity firm Splunk Inc. ...