---
title: "Upload KYB form-field document (business)"
method: POST
path: "/compliance/kyb/fields/document"
tags: ["compliance", "kyb"]
---

# Upload KYB form-field document (business)

`POST /compliance/kyb/fields/document`

Uploads a document attached to a file-type form field on the session group's KYB form.

## Request body

- KybUploadKYBFormFieldDocumentInput
  - `content_b64` string, required
  - `file_type` string
  - `filename` string, required
  - `form_field_id` string, required

## Response `200`

OK

- KybUploadKYBFormFieldDocumentOutput
  - `document_id` string

## Other responses

- `400` — Bad Request
- `401` — Unauthorized
- `403` — Forbidden
- `default` — Error response.

## Changes

- **2026-08-06** `fe2041c5ba86` — 1 warning, 1 info
  - changed the pattern of the request property `form_field_id` from `^ffld_[0-9a-hjkmnp-tv-z]{26}$` to `^ffld_[0-7][0-9a-hjkmnp-tv-z]{25}$`
  - the `document_id` response's property pattern was changed from `^doc_[0-9a-hjkmnp-tv-z]{26}$` to `^doc_[0-7][0-9a-hjkmnp-tv-z]{25}$` for the status `200`

[Change history](https://skmtc.dev/stablesea/apis/stable-sea-backend/changes/compliance/kyb/fields/document/post.md)

---

[API](https://skmtc.dev/stablesea/apis/stable-sea-backend.md) · [All operations](https://skmtc.dev/stablesea/apis/stable-sea-backend/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/stablesea/stable-sea-backend/revisions/78f4fe30ef9c/schema)