A supermajority vote is an approval requirement set higher than a simple majority of the relevant voting power, typically 66.67% (two-thirds) or 75% (three-fourths). It applies to outstanding shares, the relevant class of preferred, the board, or other defined voting body, used for corporate matters significant enough that a simple majority is considered insufficient protection against changes affecting minority interests. It is a structural protection that creates higher barriers to action on matters where minority stockholders or specific share classes need elevated consent rights.
The contexts where supermajority votes appear in venture-backed companies: