The spokesman would not immediately identify the connectivity provider or other companies involved.
There was no estimated time for the sites to be back up and running.
The Herald attempted to run a search on the Companies Office around 12.30pm, only to be met with a message that it was offline for maintenance and expected to be operational again by 1pm.
That did not seem the end of the world. Web glitches happen.
But then the offline notice was updated for a 1.30pm return time, then 2pm, then 2.30pm, then 3pm, then 3.30pm, then 4pm before it was dropped in favour of an open-ended message.
MBIE did not issue an alert on Twitter until after 5pm.
Lowndes Jordon partner Rick Shera complained on Twitter that IPONZ (the Intellectual Property Office) was also offline, and had been since at least 12pm - and that "the Incorporated Societies site basically just says go away."