That would be almost all of them according to piratpartiet, who want to get rid of all patents. The pirate party of New Zealand simply wants to get rid of patents in industries where they actively and significantly harm innovation. The rest can stay, there's no point changing the status quo and upsetting all the patent holders and patent attorneys unless patents in those areas are actually causing a problem.
Hmmm. There is research on where patents promote innovation, but I don't know if there is research on where patents hinder innovation, and how the promotion/hindrance balances out, so if we had a referendum that suggested we shouldn't have patents where they don't significantly promote innovation, and we've got research to say where that is, there's a pretty direct conclusion of removing such patents, but I'm not sure this would follow with a referendum on removing patents where they hinder innovation, or where they hinder innovation more than they promote it. Another issue is choosing a question that can be worded simply. Dunno. At least we've got a while to figure this out though.