Contact Energy's share price dropped by 3.5 per cent this morning, partly in response to uncertainty over the future of the Tiwai Point aluminium smelter but also to an end-of-quarter price spike last week.
By late morning, shares in the former state-owned enterprise were trading at $5.50, down 20c from Thursday's closing level of $5.70 - which was a 52-week high.
Contact shares have been trading at around $5.50 for the last month or so, and traded in December at around $5.00.
One fund manager said strength in Contact's share price last week had been influenced by end-of-quarter and end-of-financial-year "window dressing'' by some investment funds.
Today's activity meant the stock was re-adjusting to around where it has traded over the last month or so after an unusual spike higher on Thursday.