The Data Vendor Landscape
Choosing a data source is a trade-off among cost, coverage, and licensing, not a search for the one best vendor.
Market data is itself a market. Bloomberg and LSEG terminals bundle data, analytics, and messaging into five-figure-per-seat subscriptions that run whole desks. Direct exchange feeds deliver the lowest latency and finest granularity but charge per venue, per entitlement, with redistribution licenses stacked on top. Aggregators and newer API-first vendors normalize all of this into one endpoint, trading cost for coverage and convenience. The real decision is cost versus coverage versus licensing: redistribution to clients or into a product can multiply the price or be barred outright. Understanding this landscape first prevents the classic mistake of building a research stack on data you are not licensed to deploy.