Before decimilization, the minimum increment was 1/16th Perhaps in theory, but not in practice. It took a $910 million class-action settlement to help change t

Before decimilization, the minimum increment was 1/16th Perhaps in theory, but not in practice. It took a $910 million class-action settlement to help change the collusion. https://www.economist.com/finance-and-economics/1998/01/15/collusion-in-the-stockmarket https://www.economist.com/finance-and-economics/1998/01/15/c... Also in practice I remember the spreads being much wider, e.g. $56 bid, $57 offer.