Massey University Vice Chancellor Steve Maharey said the university's money was invested exclusively through a "major funding agency" under instructions to adhere to Massey's ethical framework.
"The background issue that any good university takes no position except in very exceptional circumstances on particular issues, because you're the host of a very diverse community of researchers who you encourage to exercise academic freedom."
Mr Maharey admitted he "wouldn't know" which companies the university has money invested in.
"Although we would be very clear with the companies we invest with, such as ANZ, about basic ethical standards, we don't really get the kind of feedback from them that would allow us to have a finely grained understanding of where they'd put the money.
"We don't ask them for that detail. Maybe we should, but we don't at the moment."
Meanwhile, this month, Glasgow University became the first academic institution in Europe to divest, with university court members voting to withdraw £18 million of its money from fossil fuels.
It brought the total of global investors who have pledged to divest to more than 800, made up of religious groups, universities, local governments and the high-profile US foundation Rockefeller Brothers.
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