BRIEF-S&P downgrades ConocoPhillips to 'A-' from 'A'; outlook negative By: Reuters: Company News April 29, 2016 at 17:07 PM EDT * ConocoPhillips downgraded to 'A-' from 'A', outlook negative; short-term and unsecured debt ratings also lowered Read More >> Related Stocks: ConocoPhillips