This pass did not establish a reliable published market-size or growth series for external specialist-model development and evaluation bought by US software firms with 20–500 employees. Broader AI investment, inference revenue and platform fundraising are useful context, but none measures that exact category.
Do not fill the gap with a generic AI-market forecast. Define the purchased work, geography, buyer size, year and double-counting rules before constructing a market estimate. A firm can buy evaluation, a production project and hosting from different suppliers; adding all their revenues without scope discipline can inflate the result.