Energy stocks extend declines a third day By: MarketWatch June 21, 2013 at 12:20 PM EDT Energy stocks extend their losses to a third session, looking to end the week off more than 2% after steep declines in the previous two days. Read More >> Related Stocks: Chevron Corp ConocoPhillips Devon Energy Energy Select Sector SPDR Exxon Mobil Marathon Petroleum Phillips 66 Royal Dutch Shell Plc ADR Tesoro Petroleum Co Williams Companies