Share price going to $1.20 suggests a distinct lack of momentum.
NAB and AMP having substantial shareholdings doesn't mean a takeover is brewing. 10% of OKN is 10m-15m which is small change to large fund managers.
From a technical analysis viewpoint this looks terrible. From July 2011, it's been a steady march downwards from $2.40. Need a positive announcement to generate some positive views - what's stopping this stock price sliding further?
