API · Manage · Rounds
Add a round investor.
Add an investor commitment to the round. Investors can be added pre-close to track the build (target raise vs. committed); they receive their share-class issuance only at close. A side letter can be attached.
Last updated
Request Body
application/json
TypeScript Definitions
Use the request body type in TypeScript.
stakeholder_idstringRequiredcommitmentobjectRequiredCurrency amount in the smallest unit (cents for USD).
amountintegerRequiredInteger in smallest unit. 100 = USD 1.00.
currencystringRequiredISO 4217 alpha-3, lower-cased.
lead_investorbooleanOptionalside_letter_document_idstringOptionalwire_received_atintegerOptionalUnix timestamp when funds were received.
metadataobjectOptionalFlat string-to-string map. Up to 50 keys. Keys: max 40 chars, charset
[A-Za-z0-9_\\-.]. Values: max 500 chars. Keys prefixed matter_ are reserved
for platform use. Metadata is retrievable but not filterable via query params.
Response Body
application/json
Request
curl -X POST "https://api.mattermode.com/v1/rounds/{id}/investors" \ -H "Content-Type: application/json" \ -d '{ "stakeholder_id": "stk_7Hpx9WxY", "commitment": { "amount": 50000, "currency": "usd" }, "lead_investor": false, "side_letter_document_id": "string", "wire_received_at": 0, "metadata": {} }'const body = JSON.stringify({ "stakeholder_id": "stk_7Hpx9WxY", "commitment": { "amount": 50000, "currency": "usd" }, "lead_investor": false, "side_letter_document_id": "string", "wire_received_at": 0, "metadata": {}})fetch("https://api.mattermode.com/v1/rounds/{id}/investors", { method: "POST", headers: { "Content-Type": "application/json" }, body})package mainimport ( "fmt" "net/http" "io/ioutil" "strings")func main() { url := "https://api.mattermode.com/v1/rounds/{id}/investors" body := strings.NewReader(`{ "stakeholder_id": "stk_7Hpx9WxY", "commitment": { "amount": 50000, "currency": "usd" }, "lead_investor": false, "side_letter_document_id": "string", "wire_received_at": 0, "metadata": {} }`) 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", "commitment": { "amount": 50000, "currency": "usd" }, "lead_investor": false, "side_letter_document_id": "string", "wire_received_at": 0, "metadata": {}}resp = requests.post( "https://api.mattermode.com/v1/rounds/id_placeholder/investors", 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", "commitment": { "amount": 50000, "currency": "usd" }, "lead_investor": false, "side_letter_document_id": "string", "wire_received_at": 0, "metadata": {}}""");HttpClient client = HttpClient.newBuilder() .connectTimeout(Duration.ofSeconds(10)) .build();HttpRequest.Builder requestBuilder = HttpRequest.newBuilder() .uri(URI.create("https://api.mattermode.com/v1/rounds/{id}/investors")) .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", "commitment": { "amount": 50000, "currency": "usd" }, "lead_investor": false, "side_letter_document_id": "string", "wire_received_at": 0, "metadata": {}}""", Encoding.UTF8, "application/json");var client = new HttpClient();var response = await client.PostAsync("https://api.mattermode.com/v1/rounds/{id}/investors", body);var responseBody = await response.Content.ReadAsStringAsync();curl --request POST 'https://api.mattermode.com/v1/rounds/id_placeholder/investors' \ --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", "commitment": { "amount": 50000, "currency": "usd" }, "lead_investor": false, "side_letter_document_id": "string", "wire_received_at": 0, "metadata": {}}'const response = await fetch("https://api.mattermode.com/v1/rounds/id_placeholder/investors", { 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", "commitment": { "amount": 50000, "currency": "usd" }, "lead_investor": false, "side_letter_document_id": "string", "wire_received_at": 0, "metadata": {} }),});if (!response.ok) { throw new Error(`Matter API ${response.status}: ${await response.text()}`);}const data = await response.json();console.log(data);Response
202Investor added.
application/json{
"resource": {
"id": "string",
"object": "round",
"entity_id": "ent_Nq3KcAbc",
"name": "Waypoint Systems, Inc.",
"kind": "seed_priced",
"stage": "term_sheet",
"created": 1745539200,
"updated": 1745539200,
"livemode": false
},
"intent": {
"id": "string",
"object": "intent",
"goal": "form_startup_ready_corporation",
"parameters": {},
"status": "draft",
"created": 1745539200,
"updated": 1745539200,
"livemode": false
},
"execution_plan": {
"steps": [
{
"operation": "string",
"status": "pending"
}
]
},
"authorization": {
"id": "string",
"object": "authorization",
"token_id": "tok_4Kj2m8pQ",
"action": "string",
"payload_hash": "string",
"status": "pending",
"expires_at": 1745539200,
"created": 1745539200,
"updated": 1745539200,
"livemode": false
},
"pending_filings": [
{
"id": "string",
"object": "filing",
"entity_id": "ent_Nq3KcAbc",
"type": "certificate_of_amendment",
"jurisdiction": "US-DE",
"status": "preparing",
"created": 1745539200,
"updated": 1745539200,
"livemode": false
}
],
"cascaded_documents": [
{
"id": "string",
"object": "document",
"entity_id": "ent_Nq3KcAbc",
"type": "certificate_of_incorporation",
"status": "draft",
"sha256": "9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08",
"version": 1,
"created": 1745539200,
"updated": 1745539200,
"livemode": false
}
],
"cascaded_resolutions": [
{
"id": "string",
"object": "resolution",
"entity_id": "ent_Nq3KcAbc",
"kind": "board_meeting",
"subject": "Approval of 2026 Equity Plan and initial pool of 2,000,000 shares",
"created": 1745539200,
"updated": 1745539200,
"livemode": false
}
],
"events_emitted": [
"string"
],
"applied_defaults": [
"string"
],
"next_steps": [
{
"endpoint": "POST /v1/entities/ent_Nq3KcAbc/tax_elections",
"reason": "Founder restricted-stock issuances require 83(b) within 30 days."
}
]
}