Could selling stock before undisclosed bad news constitute insider trading?

"impending bad news will cause the stock price to plummet? Does this constitute insider trading? Sources: Verne Kopytoff, “Equifax Board Reviews Executive Stock Sales after Data Breach,” Fortune, http://fortune.com, September 29, 2017; Jen Wieczner, “Equifax CEO Richard Smith Who Oversaw Breach to Collect $90 Million,” Fortune, http://www.fortune.com, September 26, 2017; Tom Schoenberg, Anders Melin, and Matt Robinson, “Equifax Stock Sales Are the Focus of U.S. Criminal Probe,” Bloomberg Markets, https://www.bloomberg.com, September 18, 2017; Liz Moyer, “Suspect Trading in Equifax Options before Breach Might Have Generated Millions in Profit,” CNBC, https://www.cnbc.com, September 8, 2017; Alina Selyukh, “3 Equifax Executives Sold Stock Days after Hack That Wasn’t Disclosed for a Month,” NPR, http://www.npr.org, September 8, 2017; Anders Melin, “Three Equifax Managers Sold Stock Before Cyber Hack Revealed,” Bloomberg News, https://www.bloomberg.com, September 7,"