For investors who measure their investment horizon in years rather than seconds, the US equity market has become an inhospitable place. Those wanting to buy and sell big stakes in companies have found that process challenged by a market structure increasingly designed for the smaller orders created by algorithmic traders.

Nine of the world's largest asset managers, led by Fidelity and including BlackRock, JP Morgan Asset Management and Invesco, have decided enough is enough. On November 3, they launched their own off-exchange trading venue, Luminex, owned by and run solely for buyside firms with a long-term investment horizon.