The Pike River Royal Commission of Inquiry could reconvene, after a request from the lawyers representing former chief executive Peter Whittall and some of the directors.
The commission was due to report back by September 28, but Mr Whittall's lawyer Stacey Shortall has asked that it be recalled to hear evidence from three witnesses.
For now, the new evidence is on the secure commission website and remains confidential, but it is all from former Pike River Coal Ltd technical staff member Udo Renk and middle managers Terry Moynihan and Greg Borichevsky.
The new evidence has come to light three months after the commission closed its public hearings in Greymouth.
Ms Shortall wants to be able to cross-examine the men, test the weight of the evidence, and ensure there is as much evidence before the commission as possible.