The Auckland High Court has been hearing evidence concerning the legality of timber imported by Lumberbank before its expulsion from the New Zealand Timber Importers Association in May.
The Malaysian-owned company is contesting its expulsion for allegedly importing logged sawn timber illegally, mainly from Papua New Guinea.
The New Zealand association has made a commitment to source timber only from certified sustainably managed forests.
The Lumberbank is a subsidiary of Ernslaw One which is owned by Malaysian logging company Rimbunan Hijau - the key logging company in PNG.
Grant Rosoman of the interest group Greenpeace, who has accused Rimbunan Hijau of trading timber from illegal operations, says the timber industry is starting to look more at their timber sources.
"The information that the Timber Importers Association has put in their affidavits is the World Bank's independent review team reports and evidence such as this that has very clearly identified irregularities in procedures and breaches of forestry regulations in PNG and that's what they have based their case on."