More than half of the Vector investors who sold their shares at bargain basement prices over the Christmas break have been given a chance to change their minds.
More than 300 investors responded to an unsolicited offer from Christchurch man Bernard Whimp and more than 370,000 shares in the energy and lines company were sold to Mr Whimp's company Energy Securities.
The share buy-up was part of a mass mailout by Energy Securities over the Christmas break.
The company also offered to buy shareholdings in Telecom, Nuplex Industries, Guiness Peat Group, Contact Energy and Fletcher Building, typically for about two thirds of the market value.
Vector says 170 of the investors who agreed to sell their stakes failed to fill in the share transfer form correctly. As a result, the transactions have not been completed.
Vector chairman Michael Stiassney says the company has taken the unprecedented move of contacting all 170 investors, alerting them to the error and urging them to rethink.
The low-ball offers from Energy Securities are not illegal but have been widely criticised by industry insiders.