Historical clue formulations

• Brokerage sale: Abbr. — 2018-08-22
• Purchase via Charles Schwab: Abbr. — 2017-05-21
• Nasdaq unit: Abbr. — 2013-10-24
• Exchange purchase: Abbr. — 2012-06-24
• Nasdaq listing: Abbr. — 2011-10-15
• Nasdaq buy: Abbr. — 2009-04-29
• Co. shares — 2006-12-31
• Corp. shares — 2004-01-04