Insurers IAG and Tower are headed to court to challenge the Earthquake Commission's payouts for Canterbury earthquake claimants whose properties had land issues.
The two separate cases centre around the difference between what the insurers paid out to settle those claims and how the EQC calculated the payments made to some private insurers.
In order to speed up the claims process IAG, whose brands include AMI and State Insurance, and some other insurers decided to reinstate or cash settle claims for customers with properties facing increased liquefaction vulnerability instead of insisting they go to EQC first to get their land either fixed up and paid out on.
The insurers claim they did this on the understanding that EQC would compensate them for the costs.
But now the EQC has made the payments and published its methodologies the insurers say they have discovered there is a "fundamental difference" in the approach to the land settlements between private insurers and EQC.