… and if you get ISA eligibility wrong then HMRC can revoke your ISA manager status… or you can run the PR gauntlet of having to run an ‘ISA Repair’ process… which is costly and an admin headache… like T212 had to recently when they misclassified about 90 stocks… but still misclassify ‘a lot’
… FT by comparison are pretty good… but still misclassify a good handful.
UNSURPRISINGLY () FinKi make an API that auto tracks HMRC ISA rules and identifies if a stock (adr, warrant, right, gdr, ord, anything) is Eligilble… I don’t think you can get that service anywhere else… if you can I’d reckon it’s wrong. (Who really tracks what tier a Russian stock is listed on or what reporting accounting standards a Swiss stock adheres to? Yes, they’re real examples to demonstrate the crazy level of detail you need for every stock on every exchange)
ISA rules are complex and ever changing.
Why bother running it in house? Too much hassle.