MSCI, the research house and equity index provider, is to broaden its investigation of non-voting shares.

The indexer launched a consultation on unequal voting rights in June this year following Snap Inc’s decision to issue shares in an IPO that carried no voting rights at all.

The initial consultation had looked at voting where company-level voting power was less than 25%. MSCI has already reported that most of the market participants it consulted would support exclusion of unequal voting rights from its indices.

In a statement this week MSCI said its investigation would now be extended to “include a discussion on the treatment of all types of unequal voting structures”.

MSCI said: “In particular, the consultation will focus on the theoretical and practical issues of the application of a ‘one share, one vote’ principle to the investment opportunity set of international institutional investors.”

It added: “This decision follows a consultation with international institutional investors on the treatment of non-voting shares in the MSCI Equity Indexes.”