First Leeward

Companies

Upload application documents

POSThttps://api.firstleeward.com/v0/companies/:id/applications/documents

Uploads one company supporting document type for a Universal KYB application. Set documentType to a pending company document from nextAction and attach its file(s) as files. Upload one type per request. Beneficial-owner identity documents use POST /companies/:id/related-persons/:personId/documents.

Authorizations

Authorizationstring · headerrequired

API key as Bearer token, e.g. Bearer YOUR_API_KEY

Headers

Leeward-Versionenum<string>required

API version (YYYY-MM-DD). Available option: 2026-09-18

Path Parameters

idstring<uuid>required

Unique company identifier

Body

multipart/form-data

documentTypestringrequired

Which supporting document this upload is for (one type per request; from the pending documents in nextAction)

Available options:CERTIFICATE_OF_INCORPORATIONCOMPANY_PROFILESHAREHOLDING_CHARTREGISTER_OF_DIRECTORSBUSINESS_REGISTRYSOURCE_OF_FUNDSSOURCE_OF_WEALTH
filesany | any[]required

The document file(s) for this type. Send a single file, or repeat the files field (max 5, 5MB total).

Response

200Application state after uploading a company document
documentTypestringrequired

Document type that was uploaded

Available options:CERTIFICATE_OF_INCORPORATIONCOMPANY_PROFILESHAREHOLDING_CHARTREGISTER_OF_DIRECTORSBUSINESS_REGISTRYSOURCE_OF_FUNDSSOURCE_OF_WEALTH
filesobject[]required

Files stored for this upload

Show child attributes
fileIdstring<uuid>required

Identifier of the stored file

fileNamestringrequired

Original file name

nextActionobject | nullrequired

Action the client must take next, or null if none remains

Show child attributes
Option 1 · Document upload
typestringrequired
documentsobject[]required

Supporting documents to upload, each with its current upload state

Show child attributes
Option 1 · Company document
documentTypestringrequired

Company supporting document to upload

Available options:CERTIFICATE_OF_INCORPORATIONCOMPANY_PROFILESHAREHOLDING_CHARTREGISTER_OF_DIRECTORSBUSINESS_REGISTRYSOURCE_OF_FUNDSSOURCE_OF_WEALTH
statusstringrequired

This document still needs to be uploaded

Option 2 · UBO document
documentTypestringrequired

Beneficial-owner identity document

relatedPersonIdstring<uuid>required

Related person this identity document belongs to

uboDocumentTypestringrequired

Identity document type declared for this owner

Available options:PASSPORTID_CARDDRIVERS_LICENCE
statusstringrequired

This document still needs to be uploaded

Option 2 · Submit
typestringrequired
400The submitted application data was rejected
errorobjectrequired
Show child attributes
codestringrequired
messagestringrequired
detailobject | nullrequired
403The requested verification method is not enabled for this project
errorobjectrequired
Show child attributes
codestringrequired
messagestringrequired
detailobject | nullrequired
404Response for status 404
Option 1 · CompanyNotFoundError
errorobjectrequired
Show child attributes
codestringrequired
messagestringrequired
detailobject | nullrequired
Option 2 · CompanyApplicationNotFoundError
errorobjectrequired
Show child attributes
codestringrequired
messagestringrequired
detailobject | nullrequired
409Response for status 409
Option 1 · CompanyApplicationNotEditableError
errorobjectrequired
Show child attributes
codestringrequired
messagestringrequired
detailobject | nullrequired
Option 2 · CompanyApplicationNotSavedError
errorobjectrequired
Show child attributes
codestringrequired
messagestringrequired
detailobject | nullrequired