The operator of the New Zealand stock exchange says it is continuing to consider a complaint about Refining NZ's announcement to the market on Monday.
Under listing rules, a company is required to release to the market any information that a reasonable person would expect to have a material effect on the price of that firm's shares.
"NZX is continuing to consider the complaint lodged in respect of NZ Refining's announcement of 18 September. Those inquiries will follow the process for investigations as detailed in NZX's enforcement policy, and as such, NZX is not in a position to provide further information at this time," a spokeswoman for NZX said today.
"It is also important to note that not all information relevant to a listed company, its operations or commercial arrangements, will be material information for the purposes of the listing rules," she said.
"Information that is not material information is not subject to the obligations for immediate disclosure. In addition, NZX notes that information may develop over time, in circumstances where a company is required to assess that developing information to make an informed determination on its potential materiality.
Refining NZ earlier defended the speed of its announcement to the share market about the rupture of its pipeline to Wiri.
The company revealed on Facebook last Thursday that it was experiencing problems with the pipeline - but it was not until the weekend that the full extent of the problem became known.
Investor Peter Wakeman complained to the authorities about Refining NZ's slowness to tell the market about the pipeline leak, which has led to travel disruption amid a shortage in aviation fuel.
"While Refining NZ will not generally respond to media commentary, in the current circumstances regarding issues with the Refinery to Auckland pipeline, and recent media commentary concerning when Refining NZ first notified those issues to the market, Refining NZ considers it appropriate to do so," chief executive, Sjoerd Post, said to the NZX today.
"The company announced to the market as soon as it understood that the pipeline would not be operational for more than a few days," he said.
"Initially Refining NZ thought that the leak could be fixed within two days by installing a clamp on the damaged section of the pipe.
"If that had been the case the issue would have been within the ambit of operational matters and of no concern to our customers and the wider public.
"It only became apparent over the weekend that the damage to the pipeline would take longer to remedy - and accordingly we announced this to the market before it opened on Monday," he said.
NZ Refining said all going to plan, it expected to deliver jet fuel through the pipeline into Wiri between midday Sunday and midday Tuesday.
Refining NZ expects it will then take another 30 hours for the jet fuel to settle, for recertification to be obtained, and to transport it to Auckland Airport.
The rupture of the 170km-long pipeline, through which it pumps aviation fuel for use at the airport, has caused widespread disruption at the airport through flight cancellations and postponements.