API · Create · Documents
Sign the document.
Apply a stakeholder's signature to a document — directly, without going through a signing envelope. Used when only one signatory is required and a multi-party envelope would be overkill (incorporator actions, founder 83(b) elections, single-counterparty NDAs). Signature methods (signature_method) - esign — captured via the stakeholder's authenticated session or signature-token email link. Default for human signatories. SOC 2 audit trail attached. - wet_signature — the stakeholder uploads a scanned hand-signed page. Matter validates the upload and binds it to the document. Use when counterparties insist on physical signatures. - agent_authorized — a tier-3+ agent token signs on a human's behalf, using a pre-issued signature delegation. Only applicable to documents the human has pre-authorized via a Authorization of kind: signature_delegation. Multi-party documents should be sent as a SigningEnvelope instead — the envelope manages routing, sequence, and reminders; this endpoint is for single-stakeholder finalization. Prerequisites - Document must be in draft or ready_for_signature state. Returns 409 document_not_signable otherwise. - The acting stakeholder_id must be listed as a required signatory on the document. Returns 202 Accepted while the signature is recorded and the document is finalized. Idempotent via Idempotency-Key. See idempotency. See also: Documents API overview.
Last updated
Request Body
application/json
TypeScript Definitions
Use the request body type in TypeScript.
stakeholder_idstringRequiredsignature_methodstringOptional"esign""wet_signature""agent_authorized"Response Body
application/json
application/problem+json
application/problem+json
application/problem+json
Request
curl -X POST "https://api.mattermode.com/v1/documents/{id}/sign" \ -H "Content-Type: application/json" \ -d '{ "stakeholder_id": "stk_7Hpx9WxY", "signature_method": "esign" }'const body = JSON.stringify({ "stakeholder_id": "stk_7Hpx9WxY", "signature_method": "esign"})fetch("https://api.mattermode.com/v1/documents/{id}/sign", { method: "POST", headers: { "Content-Type": "application/json" }, body})package mainimport ( "fmt" "net/http" "io/ioutil" "strings")func main() { url := "https://api.mattermode.com/v1/documents/{id}/sign" body := strings.NewReader(`{ "stakeholder_id": "stk_7Hpx9WxY", "signature_method": "esign" }`) req, _ := http.NewRequest("POST", url, body) req.Header.Add("Content-Type", "application/json") res, _ := http.DefaultClient.Do(req) defer res.Body.Close() body, _ := ioutil.ReadAll(res.Body) fmt.Println(res) fmt.Println(string(body))}import requestsheaders = { "Authorization": "Bearer sk_test_4eC39HqLyjWDarjtT1zdp7dc", "Matter-Version": "2026-06-10", "Idempotency-Key": "ee7c3a9b-3f1a-4d8e-9b2a-7c5e1f0a2d4b",}payload = { "stakeholder_id": "stk_7Hpx9WxY", "signature_method": "esign"}resp = requests.post( "https://api.mattermode.com/v1/documents/doc_Z3hRk7Yc/sign", headers=headers, json=payload,)resp.raise_for_status()print(resp.json())import java.net.URI;import java.net.http.HttpClient;import java.net.http.HttpRequest;import java.net.http.HttpResponse;import java.net.http.HttpResponse.BodyHandlers;import java.time.Duration;import java.net.http.HttpRequest.BodyPublishers;var body = BodyPublishers.ofString("""{ "stakeholder_id": "stk_7Hpx9WxY", "signature_method": "esign"}""");HttpClient client = HttpClient.newBuilder() .connectTimeout(Duration.ofSeconds(10)) .build();HttpRequest.Builder requestBuilder = HttpRequest.newBuilder() .uri(URI.create("https://api.mattermode.com/v1/documents/{id}/sign")) .header("Content-Type", "application/json") .POST(body) .build();try { HttpResponse<String> response = client.send(requestBuilder.build(), BodyHandlers.ofString()); System.out.println("Status code: " + response.statusCode()); System.out.println("Response body: " + response.body());} catch (Exception e) { e.printStackTrace();}using System;using System.Net.Http;using System.Text;var body = new StringContent("""{ "stakeholder_id": "stk_7Hpx9WxY", "signature_method": "esign"}""", Encoding.UTF8, "application/json");var client = new HttpClient();var response = await client.PostAsync("https://api.mattermode.com/v1/documents/{id}/sign", body);var responseBody = await response.Content.ReadAsStringAsync();curl --request POST 'https://api.mattermode.com/v1/documents/doc_Z3hRk7Yc/sign' \ --header 'Authorization: Bearer sk_test_4eC39HqLyjWDarjtT1zdp7dc' \ --header 'Matter-Version: 2026-06-10' \ --header 'Idempotency-Key: ee7c3a9b-3f1a-4d8e-9b2a-7c5e1f0a2d4b' \ --header 'Content-Type: application/json' \ --data '{ "stakeholder_id": "stk_7Hpx9WxY", "signature_method": "esign"}'const response = await fetch("https://api.mattermode.com/v1/documents/doc_Z3hRk7Yc/sign", { method: "POST", headers: { "Authorization": "Bearer sk_test_4eC39HqLyjWDarjtT1zdp7dc", "Matter-Version": "2026-06-10", "Idempotency-Key": "ee7c3a9b-3f1a-4d8e-9b2a-7c5e1f0a2d4b", "Content-Type": "application/json", }, body: JSON.stringify({ "stakeholder_id": "stk_7Hpx9WxY", "signature_method": "esign" }),});if (!response.ok) { throw new Error(`Matter API ${response.status}: ${await response.text()}`);}const data = await response.json();console.log(data);Response
application/json{
"id": "string",
"object": "document",
"entity_id": "ent_Nq3KcAbc",
"type": "certificate_of_incorporation",
"status": "draft",
"entity_snapshot": {},
"payload": {},
"pdf_url": "https://your.app/webhooks/matter",
"sha256": "9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08",
"proof": {},
"version": 1,
"parent_document_id": "string",
"signatures": [
{}
],
"envelope_id": "string",
"sensitivity": "standard",
"metadata": {},
"created": 1745539200,
"updated": 1745539200,
"livemode": false
}{
"type": "https://mattermode.com/docs/errors/invalid_request",
"title": "Invalid request",
"status": 400,
"code": "invalid_request",
"detail": "Request body could not be parsed as JSON.",
"doc_url": "https://mattermode.com/docs/guides/errors#invalid_request",
"request_id": "req_Qw9xYz8A"
}{
"type": "https://mattermode.com/docs/errors/authentication_required",
"title": "Authentication required",
"status": 401,
"code": "authentication_required",
"detail": "No bearer token was supplied. Pass `Authorization: Bearer sk_live_...` on every request.",
"doc_url": "https://mattermode.com/docs/guides/errors#authentication_required",
"request_id": "req_Qw9xYz8A"
}{
"type": "https://mattermode.com/docs/errors/rate_limit_exceeded",
"title": "Rate limit exceeded",
"status": 429,
"code": "rate_limit_exceeded",
"detail": "Request rate exceeded for this key. Retry after `retry_after` seconds or honor the `Retry-After` header.",
"doc_url": "https://mattermode.com/docs/guides/errors#rate_limit_exceeded",
"request_id": "req_Qw9xYz8A",
"retry_after": 30
}Cascade
A single call kicks off: {"kind":"ledger_entry","type":"signature_record","timing":"immediate"} → {"kind":"document","type":"signed_document","timing":"immediate"} → {"kind":"document","type":"signature_audit_trail","timing":"immediate"}