When Greek shipowner George Economou revealed a 9.5% stake in New York-listed Performance Shipping on 25 August, one could fairly ask this question to a man who’s often been first to spot a trend: “George, what took you so long?”

Economou was just the latest to join an 18-month pattern of increased owner-on-owner investment in public companies as shipping figures seem to have partly stepped in where third-party institutional investors have stepped out.