The recent acquisition has been pitched as an avenue for growing the passive funds management business.
However, SuperLife holds some active investments in NZX-listed firms, including a 19.8 per cent stake in Wellington Drive Technologies and a 19.2 per cent stake in Energy Mad.
NZX chief executive Tim Bennett said the company was concerned about perceived conflicts, particularly with issuers in which SuperLife controlled a significant holding.
As its funds management business expanded, its governance structure was being reviewed to avoid actual and perceived conflicts of interest, he said.
Bennett said SuperLife investments including the Wellington Drive stake continued to be managed by MCA, an entity owned by SuperLife directors Michael Chamberlain and Owen Nash.
After the acquisition, Chamberlain and Nash remained directors of SuperLife. Chamberlain, SuperLife's founder, also joined NZX's management team.
Bennett said the philosophy behind ETFs, which track stock exchange indexes, was to have small, passive stakes in a large number of companies.
"Part of the strategy of that business is to move into ETFs or passive funds completely over time."
Asked if SuperLife would dispose of its active holdings, such as Wellington Drive, Bennett said the fund management business had been built up over 10 years with "a particular investment philosophy".
"People are members of those [SuperLife] schemes because of that investment philosophy or partly because of that investment philosophy so we don't want to disadvantage any members through a transition," he said. "It will be up to the investment manager to decide how to do that over time. We don't have any involvement in that."
Last month it was announced that former Commerce Minister Simon Power would step down from NZX's board because of potential conflicts of interest between his role as general manager of Westpac's private wealth business and the exchange's growth in passive funds management.