API · Exit · Corporate Transactions
Transition employees.
Same-day employee transition primitive used in Phase 2 of the acquihire cascade. For each row, flip Stakeholder.status to separated_to_acquirer, record the acquirer offer-letter pointer on Stakeholder.transition_record, and dispatch the cobra_qualifying_event_notice Document.
COBRA notices fire for every transition even when the acquirer immediately re-hires the employee with continuous coverage — the notice is a federal-law belt-and-suspenders requirement on every employer-coverage termination, not a coverage-loss signal. The notice is dispatched, the employee receives it, and the cascade records a no_action_required evidence block (evidence.test: same_day_acquirer_coverage, evidence.satisfied: true) for ERISA / DOL audit. See the payroll-and-benefits handoff for the full boundary.
Returns 202 Accepted. Idempotent via Idempotency-Key. Used directly when the orchestrator is too coarse-grained — e.g. for a partial transition where only some employees go to the acquirer.
Last updated
Query Parameters
dry_runbooleanOptionalIf true, simulate the mutation and return the would-be resource, any cascaded
resources, and a fee estimate — without side effects. Available on every mutation.
Request Body
application/json
TypeScript Definitions
Use the request body type in TypeScript.
transitionsarray<object>Requiredstakeholder_idstringRequiredacquirer_offer_letter_idstringRequiredAcquirer-side offer-letter Document pointer.
transition_datestring<date>Requiredcobra_notice_requiredbooleanOptionalDefaults to true; the COBRA notice fires for every
employer-coverage termination even when the acquirer
immediately re-hires with continuous coverage. Setting
to false is reserved for cases where the legacy
entity never offered group health coverage in the
first place — this is rare and audited.
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
application/problem+json
application/problem+json
application/problem+json
application/problem+json
application/problem+json
Request
curl -X POST "https://api.mattermode.com/v1/corporate_transactions/{id}/transition_employees" \ -H "Content-Type: application/json" \ -d '{ "transitions": [ { "stakeholder_id": "stk_emp_1", "acquirer_offer_letter_id": "doc_OfferEmp1", "transition_date": "2026-05-15", "cobra_notice_required": true }, { "stakeholder_id": "stk_emp_2", "acquirer_offer_letter_id": "doc_OfferEmp2", "transition_date": "2026-05-15", "cobra_notice_required": true } ] }'const body = JSON.stringify({ "transitions": [ { "stakeholder_id": "stk_emp_1", "acquirer_offer_letter_id": "doc_OfferEmp1", "transition_date": "2026-05-15", "cobra_notice_required": true }, { "stakeholder_id": "stk_emp_2", "acquirer_offer_letter_id": "doc_OfferEmp2", "transition_date": "2026-05-15", "cobra_notice_required": true } ]})fetch("https://api.mattermode.com/v1/corporate_transactions/{id}/transition_employees", { method: "POST", headers: { "Content-Type": "application/json" }, body})package mainimport ( "fmt" "net/http" "io/ioutil" "strings")func main() { url := "https://api.mattermode.com/v1/corporate_transactions/{id}/transition_employees" body := strings.NewReader(`{ "transitions": [ { "stakeholder_id": "stk_emp_1", "acquirer_offer_letter_id": "doc_OfferEmp1", "transition_date": "2026-05-15", "cobra_notice_required": true }, { "stakeholder_id": "stk_emp_2", "acquirer_offer_letter_id": "doc_OfferEmp2", "transition_date": "2026-05-15", "cobra_notice_required": true } ] }`) 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 = { "transitions": [ { "stakeholder_id": "stk_emp_1", "acquirer_offer_letter_id": "doc_OfferEmp1", "transition_date": "2026-05-15", "cobra_notice_required": true }, { "stakeholder_id": "stk_emp_2", "acquirer_offer_letter_id": "doc_OfferEmp2", "transition_date": "2026-05-15", "cobra_notice_required": true } ]}resp = requests.post( "https://api.mattermode.com/v1/corporate_transactions/ctx_T6yLpQ2w/transition_employees", 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("""{ "transitions": [ { "stakeholder_id": "stk_emp_1", "acquirer_offer_letter_id": "doc_OfferEmp1", "transition_date": "2026-05-15", "cobra_notice_required": true }, { "stakeholder_id": "stk_emp_2", "acquirer_offer_letter_id": "doc_OfferEmp2", "transition_date": "2026-05-15", "cobra_notice_required": true } ]}""");HttpClient client = HttpClient.newBuilder() .connectTimeout(Duration.ofSeconds(10)) .build();HttpRequest.Builder requestBuilder = HttpRequest.newBuilder() .uri(URI.create("https://api.mattermode.com/v1/corporate_transactions/{id}/transition_employees")) .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("""{ "transitions": [ { "stakeholder_id": "stk_emp_1", "acquirer_offer_letter_id": "doc_OfferEmp1", "transition_date": "2026-05-15", "cobra_notice_required": true }, { "stakeholder_id": "stk_emp_2", "acquirer_offer_letter_id": "doc_OfferEmp2", "transition_date": "2026-05-15", "cobra_notice_required": true } ]}""", Encoding.UTF8, "application/json");var client = new HttpClient();var response = await client.PostAsync("https://api.mattermode.com/v1/corporate_transactions/{id}/transition_employees", body);var responseBody = await response.Content.ReadAsStringAsync();curl --request POST 'https://api.mattermode.com/v1/corporate_transactions/ctx_T6yLpQ2w/transition_employees' \ --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 '{ "transitions": [ { "stakeholder_id": "stk_emp_1", "acquirer_offer_letter_id": "doc_OfferEmp1", "transition_date": "2026-05-15", "cobra_notice_required": true }, { "stakeholder_id": "stk_emp_2", "acquirer_offer_letter_id": "doc_OfferEmp2", "transition_date": "2026-05-15", "cobra_notice_required": true } ]}'const response = await fetch("https://api.mattermode.com/v1/corporate_transactions/ctx_T6yLpQ2w/transition_employees", { 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({ "transitions": [ { "stakeholder_id": "stk_emp_1", "acquirer_offer_letter_id": "doc_OfferEmp1", "transition_date": "2026-05-15", "cobra_notice_required": true }, { "stakeholder_id": "stk_emp_2", "acquirer_offer_letter_id": "doc_OfferEmp2", "transition_date": "2026-05-15", "cobra_notice_required": true } ] }),});if (!response.ok) { throw new Error(`Matter API ${response.status}: ${await response.text()}`);}const data = await response.json();console.log(data);Response
application/json{
"object": "employee_transition_dispatch",
"corporate_transaction_id": "ctx_AcqExample",
"transitioned_count": 2,
"cobra_notices_dispatched_count": 2,
"separated_stakeholder_ids": [
"stk_emp_1",
"stk_emp_2"
],
"events_emitted": [
"evt_stakeholder_separated_to_acquirer",
"evt_cobra_notice_sent"
]
}{
"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/not_found",
"title": "Not found",
"status": 404,
"code": "not_found",
"detail": "No entity with id `ent_Nq3KcAbc` is visible to this token.",
"doc_url": "https://mattermode.com/docs/guides/errors#not_found",
"request_id": "req_Qw9xYz8A"
}{
"type": "https://mattermode.com/docs/errors/invalid_state_transition",
"title": "Invalid state transition",
"status": 409,
"detail": "Entity ent_Nq3KcAbc is in state `dissolved` and cannot be dissolved again.",
"instance": "/requests/req_Qw9xYz8A",
"code": "invalid_state_transition",
"param": "founders[0].equity",
"doc_url": "https://mattermode.com/docs/guides/errors#invalid_state_transition",
"request_id": "req_Qw9xYz8A",
"retry_after": 30,
"authorized_by": {
"human_principal_id": "usr_4Kj2m8pQ",
"agent_id": "agt_Nq3KcAbc"
}
}{
"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
}