The company that licenses tours to New Zealand’s White Island has been found guilty of failure to minimise risk, leading to the death of 22 people in a 2019 volcanic eruption.
Whakaari Management, the final defendant in the case, will be sentenced in February.
It faces fines of up to NZ$1.5m ($928,000; £724,000) in fines.
Thirteen parties were charged, six of whom pleaded guilty and six more had their charges dismissed.
It was the largest action of its kind brought by New Zealand’s regulator Worksafe NZ.
Judge Evangelos Thomas ruled that Whakaari Management, which “managed and controlled” the active volcano, had failed in its duty to minimise risk.