B. Riley turns cautious on Tilly's

• Shares of Tilly's (NYSE:TLYS -6.3%) are showing an outsized reaction to a minor Wall Street downgrade in an indication that there's some apprehension about current levels.
• B. Riley moved to Neutral from Buy on some valuation concerns after Tilly's ran up a 59% YTD gain.
• Tilly's guided for a low single digit Q1 comp and will probably need to meet or beat that to avoid some more selling pressure.
• Management at Tilly's has drawn praise for maintaining solid margins.