Returns a paginated list of forms the caller can see, filtered by the supplied query parameters. Use taxFilingId to list every form produced by a given filing, or rootFormId to retrieve a supersession family (an original together with the forms that corrected or replaced it). filter[payeeAccountId][eq]+filter[payerAccountId][eq] together select a different, internal-only shape instead — every form instance (dynamic form engine, FormService.listForms) for that payee↔payer pair.
filter[type] is required. Tax types 1099Nec/1099Misc/T4A cannot mix with collected types. Tax filters support eq/anyOf on type, year (2021–2026), artifact status (Draft/Effective/Voided), deliveryStatus, taxFilingId, issuerAccountId, recipientAccountId, and sourceType (TaxFiling only). Other tax filters and unsupported sorts/types/operators return 422. Collected W9 retains its existing projection and accepts eq filters only; collected anyOf requests return 422. No externalId tax filter is served.