Cairn Energy's chart looks vulnerable and could be a short-term sell.

For one, Cairn has been pinned near the critical 450p support and the 50-day moving average for a month, opening the door for a downside breakout. The other bearish sign is its poor relative ratio. As noted on the right, this ratio has broken the uptrend and about to confirm a top formation.

A pre-emptive short may be opened, with the stop at 480p. Otherwise, watch to sell on a firm reak below 440p. The downside target is at 400p.