Is Diamond S Shipping next? Now that private equity investor WL Ross & Co has shed its 39.1% stake in Navigator Holdings, attention has inevitably turned to its other large shipping investment: a 22% holding in New York-listed tanker owner Diamond.

WL Ross and its owner, Invesco, have been paring their stake in Craig Stevenson-led Diamond since last year.

There is widespread market perception that it would like out of the investment entirely — sooner rather than later — in a private equity...