Five years after the great post-GFC capital-raising deluge by ASX-listed companies, it is surprising to still come across major companies that are structuring equity issues in a way that deliberately undermines retail investors.

DUET Group is a Sydney-based utilities company with a market capitalisation of $3.5 billion and a portfolio of assets that includes gas and electricity distribution businesses in Victoria as well as the Dampier-to-Bunbury gas pipeline in Western Australia.

The company was created by Macquarie Group and AMP to bid for privatised Victorian power assets in the 1990s and was floated in 2004.