In a sense. There are certainly protections they can implement against non-browser clients; what I meant is that it would be more difficult for them to implement the usual sorts of defenses you see against screen scraping since the surface area available for fingerprinting is much smaller.

We haven't seen brokerages expend significant effort on this, and the industry seems to be moving in the direction of providing more open access to APIs, so we're (cautiously) optimistic that we will be able to convince them to provide more sanctioned integration paths such that we don't need to continue playing cat-mouse with them.

What incentives do mainstream brokerages have to building public APIs? It seems to me data asymmetry is the name of the game in Wall Street and it’s no different for retail brokers.