nvestors with confidence in Signet Jewelers Ltd. SIG's long-term story showed patience and risk tolerance — but now one Wall Street analyst is no longer comfortable with a bullish stance. The Analyst RBC Capital Markets' Brian Tunick downgraded Signet Jewelers' stock rating from Outperform to Sector Perform with a price target lowered from $60 to $55. Read moreThere is some upside potential. The price will try to close the gap, but the upside potantial is rather weak. $SIG, Signet Jewelers Limited / D