diff --git a/.proofline/criteria/ac-0039.md b/.proofline/criteria/ac-0039.md
new file mode 100644
index 0000000..3b6c215
--- /dev/null
+++ b/.proofline/criteria/ac-0039.md
@@ -0,0 +1,16 @@
+---
+id: "ac-0039"
+status: active
+---
+
+# Broker ledger venue API and persistence contract
+
+## Criterion
+
+Broker ledger write는 optional nullable `execution_venue`와 `order_venue`를 수용해야 한다. `execution_venue`는 broker가 확인한 actual venue인 `KRX`, `NXT` 또는 NULL이고, `order_venue`는 original routing venue인 `KRX`, `NXT`, `SOR` 또는 NULL이다. Portfolio-hub는 두 값을 추정·상호 변환하지 않고 broker ledger row에 저장하며 POST의 new/duplicate 응답과 unified `GET /v1/portfolios/{portfolio_id}/ledger` broker item에서 그대로 반환해야 한다.
+
+## Verification
+
+- 성공 조건: `(execution_venue=NULL, order_venue=SOR)`, KRX/NXT actual과 KRX/NXT/SOR order 조합이 POST→repository→실제 PostgreSQL→POST response→unified GET에서 동일하게 round-trip되고 OpenAPI가 두 nullable enum을 노출한다.
+- 실패·경계 조건: `execution_venue=SOR`, AUTO 또는 미지원 값과 `order_venue=AUTO` 또는 미지원 값은 `422`나 DB constraint로 거부되며, order venue·시간·default로 actual venue를 채우지 않는다. 필드 생략 request는 계속 유효하고 manual/corporate-action/historical item은 NULL을 반환할 수 있다.
+- 검사 방법: schema/OpenAPI·API·repository tests와 실제 PostgreSQL round-trip/check-constraint integration을 실행하고 `LedgerEntry`·request/response·unified mapper의 end-to-end field path를 검토한다.
diff --git a/.proofline/criteria/ac-0040.md b/.proofline/criteria/ac-0040.md
new file mode 100644
index 0000000..38fd858
--- /dev/null
+++ b/.proofline/criteria/ac-0040.md
@@ -0,0 +1,16 @@
+---
+id: "ac-0040"
+status: active
+---
+
+# Idempotent venue provenance enrichment
+
+## Criterion
+
+동일 `(portfolio_id, order_id, execution_id)`의 broker ledger duplicate는 기존 portfolio row lock을 유지하면서 기존 ledger row를 `FOR UPDATE`로 선택해야 한다. 같은 transaction에서 기존 economic payload(`side`, `quantity`, `price`, `fee_amount`, `tax_amount`)를 먼저 비교하고 불일치면 metadata 변경 없이 `409`로 중단해야 한다. Economic payload가 같을 때 모든 incoming venue를 검사하여 저장값과 서로 다른 non-null이 하나라도 있으면 어느 field도 갱신하지 않고 `409`로 중단하며, 충돌이 없을 때만 저장값 NULL·incoming non-null인 venue들을 하나의 metadata-only update로 보강해야 한다. Incoming NULL은 기존 non-null을 유지해야 한다. 이 경로는 기존 ledger row를 재생성하거나 portfolio cash·asset quantity·snapshot과 WAC/PnL를 다시 변경하지 않아야 한다.
+
+## Verification
+
+- 성공 조건: execution/order venue 각각과 두 필드 동시 NULL→non-null duplicate가 같은 ledger row를 갱신하고 `200 duplicate` 최종 저장값을 반환하며 ledger row 수·cash·quantity·snapshot이 최초 `201 new` 이후 변하지 않는다. Incoming NULL replay는 기존 값을 보존한다.
+- 실패·경계 조건: economic payload 불일치는 venue 검사·update 전에 `409`이고, execution 또는 order venue의 non-null 불일치는 모든 venue 검사를 완료한 뒤 update 전에 `409`이므로 어느 venue도 부분 갱신되지 않으며 회계가 변하지 않는다. 서로 다른 concurrent backfill은 portfolio·ledger row lock 아래 하나만 성공하거나 같은 값으로 수렴하고 상충 값의 last-write-wins를 허용하지 않는다.
+- 검사 방법: API/repository idempotency·conflict tests와 실제 PostgreSQL row-lock/concurrency integration에서 final row·row count·portfolio balances·quantity·snapshot을 함께 검사한다.
diff --git a/.proofline/criteria/ac-0041.md b/.proofline/criteria/ac-0041.md
new file mode 100644
index 0000000..5907941
--- /dev/null
+++ b/.proofline/criteria/ac-0041.md
@@ -0,0 +1,16 @@
+---
+id: "ac-0041"
+status: active
+---
+
+# Venue migration and mixed-version compatibility
+
+## Criterion
+
+Venue provenance schema 변경은 `portfolio_ledger`에 nullable `execution_venue`와 `order_venue` 및 값 constraint만 additive하게 추가하고 기존 row를 backfill하거나 재해석하지 않아야 한다. 빈 DB bootstrap, 기존 Alembic head에서의 upgrade와 migration replay가 모두 같은 head schema에 수렴해야 하며, Hub가 새 필드를 optional로 먼저 수용한 뒤 core adapter가 전송을 시작하는 혼합 버전 순서에서 구·신 payload와 기존 ledger consumer가 함께 동작해야 한다.
+
+## Verification
+
+- 성공 조건: disposable PostgreSQL에서 cold bootstrap, pre-migration legacy fixture upgrade와 replay가 성공하고 기존 row의 두 venue가 NULL인 채 다른 값이 보존된다. 새 core payload와 필드를 생략한 구 payload가 모두 수용되며 manual/corporate-action, authorization, ordering/filter/cursor, joined corporate-action, WAC/PnL 회귀가 통과한다.
+- 실패·경계 조건: migration이 historical venue를 KRX/NXT/SOR로 채우거나 기존 row를 삭제·변경하거나 invalid venue를 허용하면 실패한다. Hub보다 core adapter를 먼저 배포하는 순서는 지원된다고 주장하지 않는다. Downgrade는 신규 constraint와 column만 제거하고 기존 schema를 복원한다.
+- 검사 방법: Alembic upgrade/downgrade/replay·`app/db/migrations.py` cold/legacy integration, PostgreSQL schema inventory와 기존 ledger API/repository 회귀를 실행하고 interface contract의 Hub-first rollout 문구를 검사한다.
diff --git a/.proofline/identities.json b/.proofline/identities.json
index 5f851a5..49885af 100644
--- a/.proofline/identities.json
+++ b/.proofline/identities.json
@@ -1,5 +1,5 @@
 {
   "schema_version": 1,
-  "next_line_number": 9,
-  "next_ac_number": 39
+  "next_line_number": 10,
+  "next_ac_number": 42
 }
diff --git a/.proofline/lines/line-0009/dcy-0009.md b/.proofline/lines/line-0009/dcy-0009.md
new file mode 100644
index 0000000..7471314
--- /dev/null
+++ b/.proofline/lines/line-0009/dcy-0009.md
@@ -0,0 +1,59 @@
+---
+id: "dcy-0009"
+status: confirmed
+---
+
+# Broker ledger venue provenance preservation
+
+## Problem
+
+`trex-core`는 broker가 확인한 실제 체결 거래소를 `LedgerTrade.venue`에, 최초 주문 라우팅 거래소를 `LedgerTrade.order_venue`에 구분하여 durable ledger outbox까지 보존한다. 그러나 `PortfolioHubLedger._payload()`가 두 값을 HTTP payload에서 누락하고, `portfolio-hub`의 broker ledger request·저장소·응답 모델에도 대응 필드가 없다. 이 때문에 core 내부에서 보존된 venue provenance가 portfolio-hub 전달 경계에서 소실된다.
+
+기대 상태는 core의 nullable actual execution venue와 original order venue를 추정·변환 없이 portfolio-hub에 전달하고, 기존 broker ledger 행·manual ledger·corporate action·구버전 client의 동작을 깨뜨리지 않으면서 저장·조회하는 것이다.
+
+## Evidence
+
+- `E-001` GitHub Issue #32 `https://github.com/fourblocks2020/portfolio-hub/issues/32`는 `LedgerTrade.venue -> execution_venue`, `LedgerTrade.order_venue -> order_venue` mapping, nullable historical compatibility, duplicate metadata 보강, Hub-first rollout과 venue-only 범위를 구현 계획으로 정한다.
+- `E-002` `trex-core` revision `bbdacb121c25a7539f6f9f7fe0559fc03d4542eb`의 `trex_core/application/ledger_port.py`는 `LedgerTrade.venue: Optional[str]`와 `LedgerTrade.order_venue: str`를 별도 필드로 정의한다.
+- `E-003` 같은 revision의 `trex_core/adapters/persistence/postgresql.py`와 migration `024_add_ledger_order_venue.sql`은 durable outbox에 `venue`와 `order_venue`를 별도 저장·복원하지만, `trex_core/adapters/ledger/portfolio_hub.py::PortfolioHubLedger._payload()`는 두 값을 HTTP payload에 포함하지 않는다.
+- `E-004` `portfolio-hub` revision `567d662913335a90d0de51b8e0e961b6b166d543`의 `app/schemas/v1.py::LedgerTradeRequest`·`LedgerTradeResponse`, `app/domain/models.py::LedgerEntry`, `app/repositories/portfolio_repository.py`와 `app/repositories/postgres.py`에는 execution/order venue 계약이 없다.
+- `E-005` 현재 Alembic head의 `portfolio_ledger`에는 두 venue column이 없으며 `app/db/migrations.py`와 Alembic migration이 빈 DB와 legacy DB bootstrap을 함께 소유한다.
+- `E-006` portfolio-hub active AC-0032·AC-0034·AC-0035·AC-0037은 unified ledger read, nullable source-specific facts, authorization·manual compatibility와 joined ledger 안정성을 소유하지만 broker venue의 POST validation·persistence·duplicate 보강을 명시하지 않는다. 따라서 새 observable contract는 `create` 대상이고 기존 AC는 의미를 바꾸지 않는 `satisfy` 대상이다.
+- `E-007` trex-core active AC-0019는 original `order_venue`와 nullable actual execution venue의 durable 분리, `(order_venue=SOR, venue=NULL)` 보존, 무추론 원칙과 기존 `LedgerWriter` 전달 경로를 이미 소유한다. Core 변경은 기존 AC의 의미를 바꾸지 않는 satisfy 구현이다.
+
+## Scope
+
+- `S-001` portfolio-hub에 새 active AC를 `create`하여 broker ledger request가 nullable `execution_venue` (`KRX`, `NXT`)와 nullable `order_venue` (`KRX`, `NXT`, `SOR`)를 수용하고 다른 값과 `execution_venue=SOR`를 거부하는 계약을 소유한다.
+- `S-002` `portfolio_ledger`에 nullable venue column과 allowlist constraint를 additive migration으로 추가하고 historical row를 NULL로 유지한다. 빈 DB·legacy DB migration apply/replay와 실제 PostgreSQL round-trip을 검증한다.
+- `S-003` 새 active AC를 `create`하여 broker ledger insert, duplicate lookup, domain mapping, POST 응답과 unified GET 응답이 두 venue를 추정·변환 없이 저장·반환하는 계약을 소유한다.
+- `S-004` 동일 `(portfolio_id, order_id, execution_id)` duplicate는 portfolio row lock으로 기존 동시성 경계를 유지하면서 기존 ledger row도 `FOR UPDATE`로 선택한다. 같은 transaction에서 기존 economic payload 비교를 먼저 수행해 불일치면 아무 metadata도 갱신하지 않고 `409`로 중단한다. Economic payload가 같을 때만 모든 venue의 non-null 충돌을 먼저 검사하고, 충돌이 없으면 NULL column만 incoming non-null 값으로 한 번에 보강한다. Incoming NULL은 기존 값을 지우지 않으며 이 보강은 ledger row를 재생성하거나 cash·quantity·snapshot 회계를 다시 적용하지 않는다.
+- `S-005` 기존 active AC-0032·AC-0034·AC-0035·AC-0037을 `satisfy`하여 source-neutral ordering/filter/cursor, nullable source-specific representation, owner-only authorization, manual/corporate-action 및 WAC/PnL compatibility를 유지한다.
+- `S-006` trex-core는 active AC-0019 아래 `PortfolioHubLedger._payload()`가 기존 `LedgerTrade.venue`를 `execution_venue`, 기존 `LedgerTrade.order_venue`를 `order_venue`로 전송하도록 변경한다. producer, `LedgerTrade`, outbox schema와 broker routing은 변경하지 않는다.
+- `S-007` 배포 호환 경계는 portfolio-hub 선배포 후 trex-core adapter 배포이며, 구버전 core payload와 historical/manual/corporate-action row는 venue가 NULL인 상태로 계속 유효하다.
+- `S-008` 검증은 portfolio-hub schema/API/repository/PostgreSQL migration과 concurrency/idempotency, trex-core exact adapter payload·outbox reload/retry, 양 저장소 교차 contract `201 new -> 200 duplicate -> GET /ledger`를 포함한다.
+
+## Out of Scope
+
+- `OS-001` `broker_ordered_at`, `core_observed_filled_at` 또는 다른 timestamp provenance.
+- `OS-002` trex-core `LedgerTrade`, producer, **broker execution adapter**, durable outbox schema 또는 주문 routing 변경. `PortfolioHubLedger` HTTP ledger transport adapter의 두 기존 field 직렬화는 `S-006` 범위다.
+- `OS-003` historical venue 추정·backfill, 특히 `order_venue`나 시간대로 actual execution venue를 추론하는 동작.
+- `OS-004` ledger detail endpoint, idempotency key, broker 주문 실행·라우팅 정책 변경.
+- `OS-005` production migration·deployment·runtime restart·실제 broker 주문.
+
+## Risks and Unknowns
+
+### Risks
+
+- `R-001` mixed-version rollout에서 새 core가 구 Hub에 먼저 배포되면 추가 payload field가 거부되거나 유실될 수 있다. Hub를 먼저 배포하고 기존 payload omission을 허용한다.
+- `R-002` duplicate metadata 보강이 기존 회계 transaction path를 재실행하면 잔액·수량·snapshot이 중복 반영될 수 있다. row lock과 단일 transaction에서 provenance-only update를 분리하고 회계 불변 회귀를 실행한다.
+- `R-003` repository query의 positional mapping과 joined corporate-action projection에 column을 추가할 때 기존 mapping이 어긋날 수 있다. 명시 projection·mapping 검토와 실제 PostgreSQL mixed-row 회귀로 방지한다.
+- `R-004` concurrent duplicates가 서로 다른 non-null venue를 보강하면 last-write-wins로 provenance가 변조될 수 있다. 동일 row를 잠그고 NULL-only update와 non-null conflict를 transaction 안에서 판정한다.
+
+### Assumptions
+
+- `A-001` Issue #32에 적힌 venue-only 구현 계획과 사용자의 현재 구현 지시가 제품 범위의 근거이며, 추가 timestamp나 broker lifecycle 변경은 승인되지 않았다.
+- `A-002` trex-core active AC-0019의 기존 producer/outbox 계약은 변경 없이 유지되고, 이번 core 변경은 transport 누락을 복구하는 satisfy 작업이다.
+
+### Open Questions
+
+없음. Issue #32와 현재 source에서 API naming, 값 allowlist, NULL semantics, duplicate policy, migration policy, rollout 순서와 제외 범위가 모두 결정되어 있다.
diff --git a/.proofline/lines/line-0009/line-0009.md b/.proofline/lines/line-0009/line-0009.md
new file mode 100644
index 0000000..24d6d09
--- /dev/null
+++ b/.proofline/lines/line-0009/line-0009.md
@@ -0,0 +1,4 @@
+---
+id: "line-0009"
+status: discovery
+---
diff --git a/.proofline/lines/line-0009/req-0009.md b/.proofline/lines/line-0009/req-0009.md
new file mode 100644
index 0000000..905067f
--- /dev/null
+++ b/.proofline/lines/line-0009/req-0009.md
@@ -0,0 +1,53 @@
+---
+id: "req-0009"
+status: approved
+discovery: "dcy-0009"
+criteria:
+  create:
+    - "ac-0039"
+    - "ac-0040"
+    - "ac-0041"
+  update: []
+  retire: []
+  satisfy:
+    - "ac-0032"
+    - "ac-0034"
+    - "ac-0035"
+    - "ac-0037"
+---
+
+# Broker ledger venue provenance preservation
+
+## Objective
+
+`trex-core`가 이미 durable하게 구분하는 actual execution venue와 original order-routing venue를 portfolio-hub의 broker ledger write·storage·read 경계까지 손실 없이 보존한다. Unknown actual venue와 SOR routing을 정상 조합으로 유지하고, 기존 client·historical/manual/corporate-action row·회계·조회 계약과 혼합 버전 배포의 하위호환성을 보장한다.
+
+## Scope
+
+- Broker ledger request에 optional nullable `execution_venue`와 `order_venue`를 추가한다.
+- `execution_venue`는 `KRX`, `NXT`, NULL만 허용하고 `order_venue`는 `KRX`, `NXT`, `SOR`, NULL만 허용한다.
+- `portfolio_ledger`에 두 nullable column과 같은 allowlist constraint를 additive migration으로 추가한다. 기존 row는 NULL로 유지한다.
+- Broker ledger insert·domain mapping·POST response와 unified GET broker item이 저장값을 추정·변환 없이 반환한다.
+- 동일 `(portfolio_id, order_id, execution_id)` duplicate는 portfolio row lock에 더해 기존 ledger row를 `FOR UPDATE`로 선택한다. 같은 transaction에서 기존 economic payload를 먼저 비교해 불일치면 metadata 변경 없이 `409`로 중단한다. Economic payload가 같을 때 모든 venue의 non-null 충돌을 먼저 검사하고, 충돌이 없을 때만 NULL→non-null venue를 하나의 metadata-only update로 보강한다. Incoming NULL은 기존 non-null을 지우지 않는다.
+- Metadata-only duplicate 보강은 ledger row, portfolio cash·asset quantity·snapshot, WAC/PnL 또는 corporate-action state를 다시 적용하지 않는다.
+- 기존 active AC-0032·AC-0034·AC-0035·AC-0037을 의미 변경 없이 satisfy하여 unified ordering/filter/cursor, canonical nullable representation, owner authorization, manual/corporate-action 및 joined ledger compatibility를 유지한다.
+- trex-core는 active AC-0019 아래 기존 `LedgerTrade.venue`를 `execution_venue`, `LedgerTrade.order_venue`를 `order_venue`로 HTTP payload에 전달한다. Core producer·domain·outbox schema는 변경하지 않는다.
+- 실제 PostgreSQL migration·round-trip·concurrent duplicate와 core adapter payload/reload, 교차 저장소 `201 new -> 200 duplicate -> GET /ledger` contract를 검증한다.
+
+## Constraints
+
+- `SOR`는 order routing provenance이며 actual execution venue로 저장하거나 추론하지 않는다.
+- Unknown actual venue는 NULL로 보존하고 `order_venue`, 시간 또는 historical default에서 KRX/NXT를 추론하지 않는다.
+- 기존 idempotency key와 기존 경제적 payload conflict 판정은 유지한다.
+- 추가 request field는 optional이어야 하며 구버전 core/client payload가 계속 유효해야 한다.
+- Historical, manual, corporate-action row는 두 venue가 NULL이어도 유효해야 한다.
+- Hub-first, core-adapter-second 배포 순서를 문서화하되 production rollout은 수행하지 않는다.
+- Normative Design Documents: 없음. 이 REQ와 create AC-0039~AC-0041 및 satisfy 대상 active AC가 normative specification을 소유한다.
+
+## Non-Goals
+
+- `broker_ordered_at`, `core_observed_filled_at` 또는 다른 timestamp provenance.
+- trex-core `LedgerTrade`, producer, **broker execution adapter**, outbox table/schema 또는 routing policy 변경. `PortfolioHubLedger` HTTP ledger transport adapter의 기존 venue 직렬화는 Scope에 포함한다.
+- Historical venue 추정·backfill.
+- 새로운 ledger detail endpoint 또는 idempotency key 변경.
+- Production migration·deployment·restart·실제 broker 주문.
diff --git a/app/api/v1_portfolios.py b/app/api/v1_portfolios.py
index 83cd576..6f706a6 100644
--- a/app/api/v1_portfolios.py
+++ b/app/api/v1_portfolios.py
@@ -27,6 +27,7 @@ from app.domain.models import CorporateAction, Portfolio, PortfolioComment
 from app.domain.pnl import calculate_current_wac, calculate_realized_pnl
 from app.domain.services import PORTFOLIO_NOT_FOUND_MESSAGE
 from app.repositories.factory import get_portfolio_repository_from_settings
+from app.repositories.portfolio_repository import LedgerTradeConflictError
 from app.schemas.corporate_actions import (
     CorporateActionRequest,
     CorporateActionResponse,
@@ -604,7 +605,13 @@ def _require_service_token(auth: AuthContext = Depends(require_trade_write)) ->
     return auth
 
 
-def _payloads_match(existing, body: LedgerTradeRequest) -> bool:
+def _economic_payloads_match(existing, body: LedgerTradeRequest) -> bool:
+    """Defence in depth for non-Postgres repository implementations.
+
+    The Postgres repository performs this comparison under the portfolio and
+    ledger row locks; this check preserves the public contract for test or
+    alternate repository implementations.
+    """
     return (
         existing.side == body.side
         and abs(existing.quantity - float(body.quantity)) < 1e-9
@@ -659,14 +666,21 @@ def record_ledger_trade_v1(
             executed_at=body.executed_at,
             fee_amount=float(body.fee_amount),
             tax_amount=float(body.tax_amount),
+            execution_venue=body.execution_venue,
+            order_venue=body.order_venue,
         )
+    except LedgerTradeConflictError:
+        raise HTTPException(
+            status_code=status.HTTP_409_CONFLICT,
+            detail="Duplicate key with different payload",
+        ) from None
     except HTTPException:
         raise
     finally:
         _close_repo(repo)
 
     if not created:
-        if not _payloads_match(trade, body):
+        if not _economic_payloads_match(trade, body):
             raise HTTPException(
                 status_code=status.HTTP_409_CONFLICT,
                 detail="Duplicate key with different payload",
@@ -687,6 +701,8 @@ def record_ledger_trade_v1(
         fee_amount=trade.fee_amount,
         tax_amount=trade.tax_amount,
         executed_at=trade.executed_at,
+        execution_venue=trade.execution_venue,
+        order_venue=trade.order_venue,
         recorded_at=trade.recorded_at,
         cash_balance_after=trade.cash_balance_after,
         asset_quantity_after=trade.asset_quantity_after,
@@ -827,6 +843,7 @@ def _ledger_entry_to_history_item(entry) -> LedgerHistoryItem | DividendLedgerHi
             total_cost_basis=event["total_cost_basis"], cash_balance=event["cash_balance"],
             profit_buffer=event["profit_buffer"], evidence_ref=event["evidence_ref"],
             actor_user_id=event.get("actor_user_id"), recorded_at=entry.recorded_at,
+            execution_venue=entry.execution_venue, order_venue=entry.order_venue,
         )
     action = (entry.action or entry.side or "").upper()
     if action == "DIVIDEND":
@@ -853,6 +870,8 @@ def _ledger_entry_to_history_item(entry) -> LedgerHistoryItem | DividendLedgerHi
             total_value_after=entry.total_value_after,
             target_ledger_entry_id=entry.target_ledger_entry_id,
             confirmation_evidence=entry.confirmation_evidence,
+            execution_venue=entry.execution_venue,
+            order_venue=entry.order_venue,
         )
     return LedgerHistoryItem(
         ledger_entry_id=entry.ledger_entry_id,
@@ -875,6 +894,8 @@ def _ledger_entry_to_history_item(entry) -> LedgerHistoryItem | DividendLedgerHi
         total_value_after=entry.total_value_after,
         target_ledger_entry_id=entry.target_ledger_entry_id,
         confirmation_evidence=entry.confirmation_evidence,
+        execution_venue=entry.execution_venue,
+        order_venue=entry.order_venue,
     )
 
 
diff --git a/app/db/alembic/versions/20260919_0032_ledger_venue_provenance.py b/app/db/alembic/versions/20260919_0032_ledger_venue_provenance.py
new file mode 100644
index 0000000..5037154
--- /dev/null
+++ b/app/db/alembic/versions/20260919_0032_ledger_venue_provenance.py
@@ -0,0 +1,54 @@
+"""Add nullable execution and order venue provenance to portfolio ledger.
+
+Revision ID: 20260919_0032
+Revises: 20260913_0031
+"""
+
+from alembic import op
+
+revision = "20260919_0032"
+down_revision = "20260913_0031"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    op.execute("ALTER TABLE portfolio_ledger ADD COLUMN IF NOT EXISTS execution_venue TEXT")
+    op.execute("ALTER TABLE portfolio_ledger ADD COLUMN IF NOT EXISTS order_venue TEXT")
+    op.execute(
+        """
+        DO $$ BEGIN
+            IF NOT EXISTS (
+                SELECT 1 FROM pg_constraint
+                WHERE conname = 'ck_portfolio_ledger_execution_venue'
+                  AND conrelid = 'portfolio_ledger'::regclass
+            ) THEN
+                ALTER TABLE portfolio_ledger
+                    ADD CONSTRAINT ck_portfolio_ledger_execution_venue
+                    CHECK (execution_venue IN ('KRX', 'NXT'));
+            END IF;
+        END $$
+        """
+    )
+    op.execute(
+        """
+        DO $$ BEGIN
+            IF NOT EXISTS (
+                SELECT 1 FROM pg_constraint
+                WHERE conname = 'ck_portfolio_ledger_order_venue'
+                  AND conrelid = 'portfolio_ledger'::regclass
+            ) THEN
+                ALTER TABLE portfolio_ledger
+                    ADD CONSTRAINT ck_portfolio_ledger_order_venue
+                    CHECK (order_venue IN ('KRX', 'NXT', 'SOR'));
+            END IF;
+        END $$
+        """
+    )
+
+
+def downgrade() -> None:
+    op.drop_constraint("ck_portfolio_ledger_order_venue", "portfolio_ledger", type_="check")
+    op.drop_constraint("ck_portfolio_ledger_execution_venue", "portfolio_ledger", type_="check")
+    op.drop_column("portfolio_ledger", "order_venue")
+    op.drop_column("portfolio_ledger", "execution_venue")
diff --git a/app/domain/models.py b/app/domain/models.py
index 31f653e..6bb95f6 100644
--- a/app/domain/models.py
+++ b/app/domain/models.py
@@ -6,7 +6,7 @@ from dataclasses import dataclass, field
 from datetime import date, datetime
 from decimal import Decimal
 from enum import Enum
-from typing import Any, Protocol, runtime_checkable
+from typing import Any, Literal, Protocol, runtime_checkable
 
 
 class MarketCode(str, Enum):
@@ -181,6 +181,8 @@ class LedgerEntry:
     target_ledger_entry_id: int | None = None
     confirmation_evidence: str | None = None
     actor_user_id: str | None = None
+    execution_venue: Literal["KRX", "NXT"] | None = None
+    order_venue: Literal["KRX", "NXT", "SOR"] | None = None
     corporate_action: dict[str, Any] | None = None
 
     def __post_init__(self) -> None:
diff --git a/app/repositories/portfolio_repository.py b/app/repositories/portfolio_repository.py
index 42e262a..1598bad 100644
--- a/app/repositories/portfolio_repository.py
+++ b/app/repositories/portfolio_repository.py
@@ -9,6 +9,10 @@ from typing import Protocol
 from app.domain.models import Asset, AuthToken, BrokerCredential, CorporateAction, Daemon, LedgerEntry, Portfolio, PortfolioComment, PortfolioTag, StrategySet, Tag, TokenPrincipal, User
 
 
+class LedgerTradeConflictError(ValueError):
+    """A duplicate broker-ledger key disagrees with its persisted payload."""
+
+
 class PortfolioRepository(Protocol):
     def ping(self) -> None: ...
 
@@ -324,6 +328,8 @@ class PortfolioRepository(Protocol):
         executed_at: datetime,
         fee_amount: float = 0.0,
         tax_amount: float = 0.0,
+        execution_venue: str | None = None,
+        order_venue: str | None = None,
     ) -> tuple[LedgerEntry, bool]: ...
 
     def record_manual_ledger(
diff --git a/app/repositories/postgres.py b/app/repositories/postgres.py
index 6a79bd8..4ea9a6b 100644
--- a/app/repositories/postgres.py
+++ b/app/repositories/postgres.py
@@ -40,6 +40,7 @@ from app.domain.models import (
     TokenPrincipal,
     User,
 )
+from app.repositories.portfolio_repository import LedgerTradeConflictError
 
 logger = logging.getLogger(__name__)
 _LEDGER_NUMERIC_SCALE = 8
@@ -382,7 +383,11 @@ class PostgresPortfolioRepository:
                     profit_buffer_after NUMERIC(20,8) NOT NULL DEFAULT 0,
                     strategy_set_id TEXT NOT NULL DEFAULT 'legacy',
                     note TEXT NOT NULL DEFAULT '',
-                    executed_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
+                    executed_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+                    execution_venue TEXT NULL CONSTRAINT ck_portfolio_ledger_execution_venue
+                        CHECK (execution_venue IN ('KRX', 'NXT')),
+                    order_venue TEXT NULL CONSTRAINT ck_portfolio_ledger_order_venue
+                        CHECK (order_venue IN ('KRX', 'NXT', 'SOR'))
                 )
                 """
             )
@@ -395,6 +400,33 @@ class PostgresPortfolioRepository:
             cur.execute("ALTER TABLE portfolio_ledger ADD COLUMN IF NOT EXISTS target_ledger_entry_id BIGINT")
             cur.execute("ALTER TABLE portfolio_ledger ADD COLUMN IF NOT EXISTS confirmation_evidence TEXT")
             cur.execute("ALTER TABLE portfolio_ledger ADD COLUMN IF NOT EXISTS actor_user_id TEXT")
+            cur.execute("ALTER TABLE portfolio_ledger ADD COLUMN IF NOT EXISTS execution_venue TEXT")
+            cur.execute("ALTER TABLE portfolio_ledger ADD COLUMN IF NOT EXISTS order_venue TEXT")
+            cur.execute(
+                """
+                DO $$
+                BEGIN
+                    IF NOT EXISTS (
+                        SELECT 1 FROM pg_constraint
+                        WHERE conname = 'ck_portfolio_ledger_execution_venue'
+                          AND conrelid = 'portfolio_ledger'::regclass
+                    ) THEN
+                        ALTER TABLE portfolio_ledger
+                        ADD CONSTRAINT ck_portfolio_ledger_execution_venue
+                        CHECK (execution_venue IS NULL OR execution_venue IN ('KRX', 'NXT'));
+                    END IF;
+                    IF NOT EXISTS (
+                        SELECT 1 FROM pg_constraint
+                        WHERE conname = 'ck_portfolio_ledger_order_venue'
+                          AND conrelid = 'portfolio_ledger'::regclass
+                    ) THEN
+                        ALTER TABLE portfolio_ledger
+                        ADD CONSTRAINT ck_portfolio_ledger_order_venue
+                        CHECK (order_venue IS NULL OR order_venue IN ('KRX', 'NXT', 'SOR'));
+                    END IF;
+                END $$;
+                """
+            )
             cur.execute(
                 """
                 DO $$
@@ -2018,6 +2050,8 @@ class PostgresPortfolioRepository:
         executed_at,
         fee_amount: float = 0.0,
         tax_amount: float = 0.0,
+        execution_venue: str | None = None,
+        order_venue: str | None = None,
     ) -> tuple[LedgerEntry, bool]:
         self.ensure_schema()
         side_normalized = str(side).lower()
@@ -2078,16 +2112,70 @@ class PostgresPortfolioRepository:
                             executed_at, recorded_at,
                             cash_balance_after::float8, asset_quantity_after::float8,
                             total_value_after::float8, profit_buffer_after::float8,
-                            strategy_set_id, note
+                            strategy_set_id, note, source, target_ledger_entry_id,
+                            confirmation_evidence, actor_user_id, execution_venue, order_venue
                         FROM portfolio_ledger
                         WHERE portfolio_id = %s AND order_id = %s AND execution_id = %s
                         ORDER BY recorded_at DESC, ledger_entry_id DESC
                         LIMIT 1
+                        FOR UPDATE
                         """,
                         (portfolio_id, order_id, execution_id),
                     )
                     existing = cur.fetchone()
                     if existing is not None:
+                        economic_payload_matches = (
+                            existing[4] == side_normalized
+                            and abs(float(existing[5]) - qty_float) < 1e-9
+                            and abs(float(existing[6]) - price_float) < 1e-9
+                            and abs(float(existing[7]) - fee_float) < 1e-9
+                            and abs(float(existing[8]) - tax_float) < 1e-9
+                        )
+                        if not economic_payload_matches:
+                            raise LedgerTradeConflictError("duplicate economic payload conflict")
+
+                        existing_execution_venue = existing[21]
+                        existing_order_venue = existing[22]
+                        if (
+                            existing_execution_venue is not None
+                            and execution_venue is not None
+                            and existing_execution_venue != execution_venue
+                        ) or (
+                            existing_order_venue is not None
+                            and order_venue is not None
+                            and existing_order_venue != order_venue
+                        ):
+                            raise LedgerTradeConflictError("duplicate venue payload conflict")
+
+                        enriched_execution_venue = existing_execution_venue or execution_venue
+                        enriched_order_venue = existing_order_venue or order_venue
+                        if (
+                            enriched_execution_venue != existing_execution_venue
+                            or enriched_order_venue != existing_order_venue
+                        ):
+                            cur.execute(
+                                """
+                                UPDATE portfolio_ledger
+                                SET execution_venue = %s, order_venue = %s
+                                WHERE ledger_entry_id = %s AND recorded_at = %s
+                                RETURNING
+                                    ledger_entry_id, portfolio_id, order_id, execution_id, side,
+                                    quantity::float8, price::float8,
+                                    fee_amount::float8, tax_amount::float8,
+                                    executed_at, recorded_at,
+                                    cash_balance_after::float8, asset_quantity_after::float8,
+                                    total_value_after::float8, profit_buffer_after::float8,
+                                    strategy_set_id, note, source, target_ledger_entry_id,
+                                    confirmation_evidence, actor_user_id, execution_venue, order_venue
+                                """,
+                                (
+                                    enriched_execution_venue,
+                                    enriched_order_venue,
+                                    existing[0],
+                                    existing[10],
+                                ),
+                            )
+                            existing = cur.fetchone()
                         # Duplicate: do not insert a new row, do not mutate the portfolio.
                         # OQ-4 (b): return the CURRENT authoritative portfolio state so the
                         # caller always syncs to the latest balances, not the first-call snapshot.
@@ -2102,12 +2190,13 @@ class PostgresPortfolioRepository:
                         portfolio_id, recorded_at, ledger_entry_id, order_id, execution_id,
                         side, price, quantity, fee_amount, tax_amount,
                         cash_balance_after, asset_quantity_after, total_value_after,
-                        profit_buffer_after, strategy_set_id, note, executed_at
+                        profit_buffer_after, strategy_set_id, note, executed_at,
+                        execution_venue, order_venue
                     ) VALUES (
                         %s, NOW(), DEFAULT, %s, %s,
                         %s, %s, %s, %s, %s,
                         %s, %s, %s,
-                        %s, %s, %s, %s
+                        %s, %s, %s, %s, %s, %s
                     )
                     RETURNING
                         ledger_entry_id, portfolio_id, order_id, execution_id, side,
@@ -2116,7 +2205,8 @@ class PostgresPortfolioRepository:
                         executed_at, recorded_at,
                         cash_balance_after::float8, asset_quantity_after::float8,
                         total_value_after::float8, profit_buffer_after::float8,
-                        strategy_set_id, note
+                        strategy_set_id, note, source, target_ledger_entry_id,
+                        confirmation_evidence, actor_user_id, execution_venue, order_venue
                     """,
                     (
                         portfolio_id,
@@ -2134,6 +2224,8 @@ class PostgresPortfolioRepository:
                         strategy_set_id,
                         "",
                         executed_at,
+                        execution_venue,
+                        order_venue,
                     ),
                 )
                 row = cur.fetchone()
@@ -2182,6 +2274,16 @@ class PostgresPortfolioRepository:
             target_ledger_entry_id=int(row[18]) if len(row) > 18 and row[18] is not None else None,
             confirmation_evidence=row[19] if len(row) > 19 else None,
             actor_user_id=row[20] if len(row) > 20 else None,
+            execution_venue=(
+                row[21]
+                if len(row) > 21 and row[21] in {None, "KRX", "NXT"}
+                else None
+            ),
+            order_venue=(
+                row[22]
+                if len(row) > 22 and row[22] in {None, "KRX", "NXT", "SOR"}
+                else None
+            ),
         )
 
     def reset(self, portfolio_id: str) -> Portfolio:
@@ -2492,7 +2594,8 @@ class PostgresPortfolioRepository:
                         SELECT ledger_entry_id, portfolio_id, order_id, execution_id, side, quantity, price,
                                fee_amount, tax_amount, executed_at, recorded_at, cash_balance_after,
                                asset_quantity_after, total_value_after, profit_buffer_after, strategy_set_id,
-                               note, source, target_ledger_entry_id, confirmation_evidence, actor_user_id
+                               note, source, target_ledger_entry_id, confirmation_evidence, actor_user_id,
+                       execution_venue, order_venue
                         FROM portfolio_ledger
                         WHERE portfolio_id = %s AND ledger_entry_id = %s
                         """,
@@ -2591,7 +2694,8 @@ class PostgresPortfolioRepository:
                     RETURNING ledger_entry_id, portfolio_id, order_id, execution_id, side, quantity, price,
                               fee_amount, tax_amount, executed_at, recorded_at, cash_balance_after,
                               asset_quantity_after, total_value_after, profit_buffer_after, strategy_set_id,
-                              note, source, target_ledger_entry_id, confirmation_evidence, actor_user_id
+                              note, source, target_ledger_entry_id, confirmation_evidence, actor_user_id,
+                       execution_venue, order_venue
                     """,
                     (
                         portfolio_id,
@@ -2623,7 +2727,8 @@ class PostgresPortfolioRepository:
                 SELECT ledger_entry_id, portfolio_id, order_id, execution_id, side, quantity, price,
                        fee_amount, tax_amount, executed_at, recorded_at, cash_balance_after,
                        asset_quantity_after, total_value_after, profit_buffer_after, strategy_set_id,
-                       note, source, target_ledger_entry_id, confirmation_evidence, actor_user_id
+                       note, source, target_ledger_entry_id, confirmation_evidence, actor_user_id,
+                       execution_venue, order_venue
                 FROM portfolio_ledger
                 WHERE portfolio_id = %s AND source = 'manual'
                 ORDER BY recorded_at DESC, ledger_entry_id DESC
@@ -2661,6 +2766,7 @@ class PostgresPortfolioRepository:
                        ledger.asset_quantity_after, ledger.total_value_after, ledger.profit_buffer_after,
                        ledger.strategy_set_id, ledger.note, ledger.source, ledger.target_ledger_entry_id,
                        ledger.confirmation_evidence, ledger.actor_user_id,
+                       ledger.execution_venue, ledger.order_venue,
                        ca.corporate_action_id, ca.action_type, ca.effective_date,
                        ca.quantity_before, ca.quantity_after, ca.average_price_before,
                        ca.average_price_after, ca.total_cost_basis, ca.cash_balance,
@@ -2676,8 +2782,8 @@ class PostgresPortfolioRepository:
             result = []
             for row in cur.fetchall():
                 entry = self._row_to_ledger_entry(row)
-                if row[21] is not None:
-                    entry.corporate_action = {"corporate_action_id": str(row[21]), "action_type": row[22], "effective_date": row[23], "quantity_before": Decimal(str(row[24])), "quantity_after": Decimal(str(row[25])), "average_price_before": Decimal(str(row[26])), "average_price_after": Decimal(str(row[27])), "total_cost_basis": Decimal(str(row[28])), "cash_balance": Decimal(str(row[29])), "profit_buffer": Decimal(str(row[30])), "evidence_ref": row[31], "actor_user_id": row[32]}
+                if row[23] is not None:
+                    entry.corporate_action = {"corporate_action_id": str(row[23]), "action_type": row[24], "effective_date": row[25], "quantity_before": Decimal(str(row[26])), "quantity_after": Decimal(str(row[27])), "average_price_before": Decimal(str(row[28])), "average_price_after": Decimal(str(row[29])), "total_cost_basis": Decimal(str(row[30])), "cash_balance": Decimal(str(row[31])), "profit_buffer": Decimal(str(row[32])), "evidence_ref": row[33], "actor_user_id": row[34]}
                 result.append(entry)
             return result
 
diff --git a/app/schemas/portfolio.py b/app/schemas/portfolio.py
index 42b3174..572b932 100644
--- a/app/schemas/portfolio.py
+++ b/app/schemas/portfolio.py
@@ -37,6 +37,8 @@ class LedgerEntryResponse(BaseModel):
     profit_buffer_after: float = 0.0
     strategy_set_id: str = "manual"
     note: str = ""
+    execution_venue: Literal["KRX", "NXT"] | None = None
+    order_venue: Literal["KRX", "NXT", "SOR"] | None = None
 
 
 class PortfolioBase(BaseModel):
diff --git a/app/schemas/v1.py b/app/schemas/v1.py
index 278a9bc..c786f3a 100644
--- a/app/schemas/v1.py
+++ b/app/schemas/v1.py
@@ -108,6 +108,8 @@ class UserInfoResponse(BaseModel):
 # ---------------------------------------------------------------------------
 
 class LedgerTradeRequest(BaseModel):
+    model_config = ConfigDict(extra="forbid")
+
     order_id: str = Field(..., min_length=1)
     execution_id: str = Field(..., min_length=1)
     side: Literal["buy", "sell"]
@@ -116,6 +118,8 @@ class LedgerTradeRequest(BaseModel):
     fee_amount: Decimal = Field(default=Decimal(0), ge=0)
     tax_amount: Decimal = Field(default=Decimal(0), ge=0)
     executed_at: datetime
+    execution_venue: Literal["KRX", "NXT"] | None = None
+    order_venue: Literal["KRX", "NXT", "SOR"] | None = None
 
 
 class LedgerTradeResponse(BaseModel):
@@ -129,6 +133,8 @@ class LedgerTradeResponse(BaseModel):
     fee_amount: float
     tax_amount: float
     executed_at: datetime
+    execution_venue: Literal["KRX", "NXT"] | None = None
+    order_venue: Literal["KRX", "NXT", "SOR"] | None = None
     recorded_at: datetime | None = None
     cash_balance_after: float = 0.0
     asset_quantity_after: float = 0.0
@@ -286,6 +292,8 @@ class LedgerHistoryItem(BaseModel):
     total_value_after: float | None = None
     target_ledger_entry_id: int | None = None
     confirmation_evidence: str | None = None
+    execution_venue: Literal["KRX", "NXT"] | None = None
+    order_venue: Literal["KRX", "NXT", "SOR"] | None = None
 
 
 class DividendLedgerHistoryItem(BaseModel):
@@ -311,6 +319,8 @@ class DividendLedgerHistoryItem(BaseModel):
     total_value_after: float | None = None
     target_ledger_entry_id: int | None = None
     confirmation_evidence: str | None = None
+    execution_venue: Literal["KRX", "NXT"] | None = None
+    order_venue: Literal["KRX", "NXT", "SOR"] | None = None
 
 
 class CorporateActionLedgerHistoryItem(BaseModel):
@@ -331,6 +341,8 @@ class CorporateActionLedgerHistoryItem(BaseModel):
     evidence_ref: str
     actor_user_id: str | None = None
     recorded_at: datetime
+    execution_venue: Literal["KRX", "NXT"] | None = None
+    order_venue: Literal["KRX", "NXT", "SOR"] | None = None
 
 
 class LedgerHistoryResponse(BaseModel):
diff --git a/docs/interface-contract.md b/docs/interface-contract.md
index e9140b9..ac7ec4c 100644
--- a/docs/interface-contract.md
+++ b/docs/interface-contract.md
@@ -4,8 +4,8 @@
 - Baseline Seed: .stagepilot/bootstrap/baseline.yaml
 - Status: confirmed
 - Owner: repository-maintainers
-- Last Updated (KST): 2026-05-21 00:00
-- Source Discovery / Batch: bootstrap-baseline, bat-001, bat-006, bat-008, bat-010, bat-003, bat-004, bat-005, BAT-006(dcy-004), BAT-007(dcy-004), BAT-008(dcy-004)
+- Last Updated (KST): 2026-09-19
+- Source Discovery / Batch: bootstrap-baseline, bat-001, bat-006, bat-008, bat-010, bat-003, bat-004, bat-005, BAT-006(dcy-004), BAT-007(dcy-004), BAT-008(dcy-004), ProofLine req-0009
 - Primary Runtime: mixed
 
 ## Project Summary
@@ -407,11 +407,11 @@
 ### Endpoint: `POST /v1/portfolios/{portfolio_id}/ledger/trades` (REQ-029, BAT-011; REQ-033 column rename BAT-015)
 
 - Auth: DB service token with `trade-write` permission; `daemon_id IS NULL` → HTTP 403 fail-closed
-- Request: `LedgerTradeRequest` — `order_id`, `execution_id`, `side` (buy|sell), `quantity`, `price`, `fee_amount`, `tax_amount`, `executed_at`
-- Response: HTTP 201 + `LedgerTradeResponse` with `status="new"`; HTTP 200 + `status="duplicate"` for idempotent replay; HTTP 409 for conflicting payload
-- `LedgerTradeResponse` fields: `ledger_entry_id`, `portfolio_id` (renamed from `asset_id` by REQ-033 / dcy-005 — schema and DB column now match in meaning), `order_id`, `execution_id`, `side`, `quantity`, `price`, `fee_amount`, `tax_amount`, `executed_at`, `recorded_at`, `status`
-- Error: HTTP 403 (no daemon_id on token, portfolio unassigned, daemon mismatch); HTTP 404 (non-existent portfolio); HTTP 409 (disabled portfolio or payload conflict)
-- Idempotency key: `(portfolio_id, order_id, execution_id)` — reuses `uq_ledger_trades_idempotency` constraint
+- Request: `LedgerTradeRequest` — `order_id`, `execution_id`, `side` (buy|sell), `quantity`, `price`, `fee_amount`, `tax_amount`, `executed_at`, optional `execution_venue` (`KRX|NXT|null`), optional `order_venue` (`KRX|NXT|SOR|null`). `SOR` is routing provenance only and is rejected as `execution_venue`; the service never infers actual execution venue from routing venue or time.
+- Response: HTTP 201 + `LedgerTradeResponse` with `status="new"`; HTTP 200 + `status="duplicate"` for idempotent replay; both responses and broker items from `GET /v1/portfolios/{portfolio_id}/ledger` return persisted `execution_venue` and `order_venue`; HTTP 409 for conflicting payload
+- `LedgerTradeResponse` fields: `ledger_entry_id`, `portfolio_id` (renamed from `asset_id` by REQ-033 / dcy-005 — schema and DB column now match in meaning), `order_id`, `execution_id`, `side`, `quantity`, `price`, `fee_amount`, `tax_amount`, `executed_at`, `execution_venue`, `order_venue`, `recorded_at`, `status`
+- Error: HTTP 403 (no daemon_id on token, portfolio unassigned, daemon mismatch); HTTP 404 (non-existent portfolio); HTTP 409 (disabled portfolio, economic-payload conflict, or conflicting non-null venue); HTTP 422 (unsupported venue or unknown request field)
+- Idempotency key: `(portfolio_id, order_id, execution_id)` — reuses `uq_ledger_trades_idempotency` constraint. Equal economic payloads may atomically enrich only NULL venue metadata; incoming NULL never erases persisted metadata, conflicting non-null values return HTTP 409, and metadata enrichment never reapplies accounting.
 - **구 path `POST /v1/assets/{asset_id}/ledger/trades`**: BAT-011에서 제거됨. 호출 시 HTTP 404.
 
 ### Endpoint: `POST /v1/portfolios/{portfolio_id}/ledger/manual` (REQ-056, BAT-024)
diff --git a/scripts/image_release.py b/scripts/image_release.py
index 56729a4..9877966 100755
--- a/scripts/image_release.py
+++ b/scripts/image_release.py
@@ -25,8 +25,8 @@ COMMIT_RE = re.compile(r"^[0-9a-f]{40}$")
 VERSION_REF_RE = re.compile(r"^refs/tags/v(0|[1-9][0-9]*)\.(0|[1-9][0-9]*)\.(0|[1-9][0-9]*)$")
 IMAGE_ID_RE = re.compile(r"^sha256:[0-9a-f]{64}$")
 DIGEST_RE = re.compile(r"(?:^|\s)digest:\s*(sha256:[0-9a-f]{64})(?:\s|$)")
-EXPECTED_MIGRATION_COUNT = 31
-EXPECTED_ALEMBIC_HEAD = "20260913_0031"
+EXPECTED_MIGRATION_COUNT = 32
+EXPECTED_ALEMBIC_HEAD = "20260919_0032"
 
 @dataclass(frozen=True)
 class Result:
diff --git a/tests/release/test_image_release.py b/tests/release/test_image_release.py
index f07cfc0..ae28afc 100644
--- a/tests/release/test_image_release.py
+++ b/tests/release/test_image_release.py
@@ -33,8 +33,8 @@ class RecordingRunner:
         if command[:3] == ["docker", "run", "--rm"] and "urllib.request" in command[-1]:
             enabled = "TARGET:8000" not in command[-1] and "plain" not in command[-1]
             return image_release.Result('{"status":"ok","db_enabled":' + str(enabled).lower() + '}')
-        if command[:3] == ["docker", "run", "--rm"] and "alembic_version" in command[-1]: return image_release.Result("20260913_0031\n")
-        if command[:3] == ["docker", "run", "--rm"] and "health-check" in command: return image_release.Result('{"database_revision":"20260913_0031"}\n')
+        if command[:3] == ["docker", "run", "--rm"] and "alembic_version" in command[-1]: return image_release.Result("20260919_0032\n")
+        if command[:3] == ["docker", "run", "--rm"] and "health-check" in command: return image_release.Result('{"database_revision":"20260919_0032"}\n')
         return image_release.Result()
 
 def artifacts(tmp_path: Path):
@@ -74,12 +74,16 @@ def test_project_version_must_match_release_tag(tmp_path):
 def test_installed_smoke_has_import_cli_exact_inventory_and_cleanup():
     inventory = tuple(
         [f"202601{i:02d}_{i:04d}_migration.py" for i in range(1, 30)]
-        + ["20260820_0030_portfolio_ledger_keyset_index.py", "20260913_0031_corporate_actions.py"]
+        + [
+            "20260820_0030_portfolio_ledger_keyset_index.py",
+            "20260913_0031_corporate_actions.py",
+            "20260919_0032_ledger_venue_provenance.py",
+        ]
     )
     runner = RecordingRunner(); image_release.smoke_installed_image("candidate", inventory, runner, 17)
     runs = [x[0] for x in runner.commands if x[0][:2] == ["docker","run"]]
     assert len(runs) == 3 and all("--read-only" in x and "none" in x for x in runs)
-    assert "migration_inventory" in runs[-1][-1] and "20260913_0031" in runs[-1][-1]
+    assert "migration_inventory" in runs[-1][-1] and "20260919_0032" in runs[-1][-1]
     assert len([x for x in runner.commands if x[0][:3] == ["docker","rm","--force"]]) == 3
 
 def _assert_exact_startup_cleanup(commands: list[list[str]]) -> None:
diff --git a/tests/release/test_release_contracts.py b/tests/release/test_release_contracts.py
index 37aaa63..0989152 100644
--- a/tests/release/test_release_contracts.py
+++ b/tests/release/test_release_contracts.py
@@ -54,7 +54,7 @@ def test_workflow_actions_are_commit_pinned_and_verify_version_is_project_derive
     assert 'RELEASE_VERSION=v0.1.3' not in verify
 
 
-def test_release_version_and_migration_contract_has_current_head_0031():
+def test_release_version_and_migration_contract_has_current_head_0032():
     project = (REPO / "pyproject.toml").read_text()
     config = (REPO / "app/core/config.py").read_text()
     migrations = sorted(
@@ -64,8 +64,8 @@ def test_release_version_and_migration_contract_has_current_head_0031():
     )
     assert 'version = "0.3.4"' in project
     assert 'app_version: str = "0.3.4"' in config
-    assert len(migrations) == 31
-    assert migrations[-1].startswith("20260913_0031_")
+    assert len(migrations) == 32
+    assert migrations[-1].startswith("20260919_0032_")
 
 def test_dockerignore_is_deny_by_default_required_inputs_only():
     lines=(REPO/".dockerignore").read_text().splitlines(); assert lines[0]=="**"
diff --git a/tests/test_bat025_portfolio_ledger_manual_metadata_migration.py b/tests/test_bat025_portfolio_ledger_manual_metadata_migration.py
index 889aeb8..8b6bf62 100644
--- a/tests/test_bat025_portfolio_ledger_manual_metadata_migration.py
+++ b/tests/test_bat025_portfolio_ledger_manual_metadata_migration.py
@@ -34,7 +34,7 @@ from app.repositories.postgres import PortfolioDBConfig, PostgresPortfolioReposi
 
 _LOCAL_DSN_ENV = "BAT025_LOCAL_POSTGRES_DSN"
 _LOOPBACK_HOSTS = {"127.0.0.1", "localhost", "::1"}
-_HEAD = "20260715_0028"
+_HEAD = "20260919_0032"
 _PRE_BAT025 = "20260628_0027"
 
 
@@ -138,6 +138,26 @@ def _metadata_columns(settings: Settings) -> dict[str, tuple[str, str, str | Non
         return {row[0]: (row[1], row[2], row[3]) for row in cur.fetchall()}
 
 
+def _venue_columns(settings: Settings) -> dict[str, tuple[str, str, str | None]]:
+    with psycopg.connect(
+        host=settings.active_db_host,
+        port=settings.active_db_port,
+        dbname=settings.active_db_name,
+        user=settings.active_db_user,
+        password=settings.active_db_password,
+        sslmode=settings.active_db_sslmode,
+    ) as conn, conn.cursor() as cur:
+        cur.execute(
+            """
+                SELECT column_name, data_type, is_nullable, column_default
+                FROM information_schema.columns
+                WHERE table_schema = 'public' AND table_name = 'portfolio_ledger'
+                  AND column_name IN ('execution_venue', 'order_venue')
+                """
+        )
+        return {row[0]: (row[1], row[2], row[3]) for row in cur.fetchall()}
+
+
 def _seed_portfolio(repo: PostgresPortfolioRepository, suffix: str) -> str:
     portfolio_id = f"bat025-{suffix}"
     user_id = f"bat025-user-{suffix}"
@@ -215,14 +235,79 @@ def test_upgrade_from_pre_0028_preserves_business_data_and_backfills_source(
         "confirmation_evidence": ("text", "YES", None),
         "actor_user_id": ("text", "YES", None),
     }
+    assert _venue_columns(isolated_settings) == {
+        "execution_venue": ("text", "YES", None),
+        "order_venue": ("text", "YES", None),
+    }
     with repo._connect().cursor() as cur:
         cur.execute(
-            "SELECT COUNT(*), side, price::text, quantity::text, note, source "
-            "FROM portfolio_ledger GROUP BY side, price, quantity, note, source"
+            "SELECT COUNT(*), side, price::text, quantity::text, note, source, "
+            "execution_venue, order_venue FROM portfolio_ledger "
+            "GROUP BY side, price, quantity, note, source, execution_venue, order_venue"
         )
-        count, side, price, quantity, note, source = cur.fetchone()
+        row = cur.fetchone()
+    assert row is not None
+    count, side, price, quantity, note, source, execution_venue, order_venue = row
     assert count == before_count
     assert (side, price, quantity, note, source) == ("buy", "123.45000000", "7.00000000", "preserve-me", "broker")
+    assert (execution_venue, order_venue) == (None, None)
+
+    with pytest.raises(psycopg.errors.CheckViolation), repo._connect().cursor() as cur:
+        cur.execute(
+            "UPDATE portfolio_ledger SET execution_venue = 'SOR' WHERE portfolio_id = %s",
+            (portfolio_id,),
+        )
+
+    upgrade_to_head(isolated_settings)
+    assert _current_revision(isolated_settings) == _HEAD
+    repo.close()
+
+
+def test_venue_migration_downgrade_removes_only_new_columns(
+    isolated_settings: Settings,
+) -> None:
+    from alembic import command
+
+    upgrade_to_head(isolated_settings)
+    repo = _repo(isolated_settings)
+    portfolio_id = _seed_portfolio(repo, "venue-downgrade")
+    recorded_at = datetime(2026, 9, 19, tzinfo=UTC)
+    with repo._connect().cursor() as cur:
+        cur.execute(
+            """
+            INSERT INTO portfolio_ledger (
+                portfolio_id, recorded_at, side, price, quantity,
+                cash_balance_after, asset_quantity_after, total_value_after,
+                strategy_set_id, note, executed_at,
+                execution_venue, order_venue
+            ) VALUES (%s, %s, 'buy', 100, 1, 900, 1, 1000,
+                      'downgrade', 'preserve-me', %s, 'NXT', 'SOR')
+            """,
+            (portfolio_id, recorded_at, recorded_at),
+        )
+
+    command.downgrade(get_alembic_config(isolated_settings), "20260913_0031")
+
+    assert _current_revision(isolated_settings) == "20260913_0031"
+    assert _venue_columns(isolated_settings) == {}
+    with repo._connect().cursor() as cur:
+        cur.execute(
+            "SELECT COUNT(*), MIN(note) FROM portfolio_ledger WHERE portfolio_id = %s",
+            (portfolio_id,),
+        )
+        assert cur.fetchone() == (1, "preserve-me")
+
+    upgrade_to_head(isolated_settings)
+    assert _venue_columns(isolated_settings) == {
+        "execution_venue": ("text", "YES", None),
+        "order_venue": ("text", "YES", None),
+    }
+    with repo._connect().cursor() as cur:
+        cur.execute(
+            "SELECT execution_venue, order_venue FROM portfolio_ledger WHERE portfolio_id = %s",
+            (portfolio_id,),
+        )
+        assert cur.fetchone() == (None, None)
     repo.close()
 
 
diff --git a/tests/test_daemon_assignment.py b/tests/test_daemon_assignment.py
index 1723591..a68d918 100644
--- a/tests/test_daemon_assignment.py
+++ b/tests/test_daemon_assignment.py
@@ -230,6 +230,8 @@ def test_ledger_trade_201_when_daemon_matches(monkeypatch) -> None:
     trade.price = 50000.0
     trade.fee_amount = 0.0
     trade.tax_amount = 0.0
+    trade.execution_venue = None
+    trade.order_venue = None
     trade.executed_at = datetime(2026, 5, 13, 1, 0, 0, tzinfo=timezone.utc)
     trade.recorded_at = datetime(2026, 5, 13, 1, 0, 0, tzinfo=timezone.utc)
     mock_repo, client = _setup_ledger_mocks(monkeypatch, principal, portfolio, trade)
diff --git a/tests/test_ledger_consolidation_integration.py b/tests/test_ledger_consolidation_integration.py
index 441a312..0c535f3 100644
--- a/tests/test_ledger_consolidation_integration.py
+++ b/tests/test_ledger_consolidation_integration.py
@@ -12,10 +12,13 @@ from __future__ import annotations
 
 import os
 import uuid
+from concurrent.futures import ThreadPoolExecutor
 from datetime import datetime, timezone
+from threading import Barrier
 
 import pytest
 
+from app.repositories.portfolio_repository import LedgerTradeConflictError
 from app.repositories.postgres import PortfolioDBConfig, PostgresPortfolioRepository
 
 
@@ -133,6 +136,182 @@ def test_duplicate_broker_write_is_idempotent(repo, seeded_portfolio):
         assert cur.fetchone()[0] == 1
 
 
+def test_duplicate_venue_enrichment_is_metadata_only(repo, seeded_portfolio):
+    args = {
+        "portfolio_id": seeded_portfolio,
+        "order_id": "ord-venue-enrich",
+        "execution_id": "exec-venue-enrich",
+        "side": "buy",
+        "quantity": 5.0,
+        "price": 10_000.0,
+        "executed_at": _now(),
+    }
+    _first, created = repo.insert_ledger_trade(**args)
+    assert created is True
+    before = repo.get(seeded_portfolio)
+
+    enriched, created = repo.insert_ledger_trade(
+        **args,
+        execution_venue="NXT",
+        order_venue="SOR",
+    )
+
+    assert created is False
+    assert enriched.execution_venue == "NXT"
+    assert enriched.order_venue == "SOR"
+    after = repo.get(seeded_portfolio)
+    assert after.cash_balance == before.cash_balance
+    assert after.asset_quantity == before.asset_quantity
+    with repo._connect().cursor() as cur:
+        cur.execute(
+            """
+            SELECT COUNT(*), MIN(execution_venue), MIN(order_venue)
+            FROM portfolio_ledger
+            WHERE portfolio_id = %s AND order_id = %s AND execution_id = %s
+            """,
+            (seeded_portfolio, args["order_id"], args["execution_id"]),
+        )
+        assert cur.fetchone() == (1, "NXT", "SOR")
+
+
+def test_duplicate_venue_conflict_is_atomic(repo, seeded_portfolio):
+    args = {
+        "portfolio_id": seeded_portfolio,
+        "order_id": "ord-venue-conflict",
+        "execution_id": "exec-venue-conflict",
+        "side": "buy",
+        "quantity": 1.0,
+        "price": 10_000.0,
+        "executed_at": _now(),
+    }
+    repo.insert_ledger_trade(**args, execution_venue="KRX")
+    before = repo.get(seeded_portfolio)
+
+    with pytest.raises(LedgerTradeConflictError):
+        repo.insert_ledger_trade(
+            **args,
+            execution_venue="NXT",
+            order_venue="SOR",
+        )
+
+    after = repo.get(seeded_portfolio)
+    assert after.cash_balance == before.cash_balance
+    assert after.asset_quantity == before.asset_quantity
+    with repo._connect().cursor() as cur:
+        cur.execute(
+            """
+            SELECT execution_venue, order_venue
+            FROM portfolio_ledger
+            WHERE portfolio_id = %s AND order_id = %s AND execution_id = %s
+            """,
+            (seeded_portfolio, args["order_id"], args["execution_id"]),
+        )
+        assert cur.fetchone() == ("KRX", None)
+
+
+def test_duplicate_null_venues_do_not_erase_existing_values(repo, seeded_portfolio):
+    args = {
+        "portfolio_id": seeded_portfolio,
+        "order_id": "ord-venue-preserve",
+        "execution_id": "exec-venue-preserve",
+        "side": "buy",
+        "quantity": 1.0,
+        "price": 10_000.0,
+        "executed_at": _now(),
+    }
+    repo.insert_ledger_trade(
+        **args,
+        execution_venue="KRX",
+        order_venue="SOR",
+    )
+
+    duplicate, created = repo.insert_ledger_trade(**args)
+
+    assert created is False
+    assert duplicate.execution_venue == "KRX"
+    assert duplicate.order_venue == "SOR"
+
+
+def test_duplicate_economic_conflict_is_rejected(repo, seeded_portfolio):
+    args = {
+        "portfolio_id": seeded_portfolio,
+        "order_id": "ord-economic-conflict",
+        "execution_id": "exec-economic-conflict",
+        "side": "buy",
+        "quantity": 1.0,
+        "price": 10_000.0,
+        "executed_at": _now(),
+    }
+    repo.insert_ledger_trade(**args)
+
+    with pytest.raises(LedgerTradeConflictError):
+        repo.insert_ledger_trade(**{**args, "quantity": 2.0}, order_venue="SOR")
+
+    with repo._connect().cursor() as cur:
+        cur.execute(
+            """
+            SELECT quantity::float8, order_venue
+            FROM portfolio_ledger
+            WHERE portfolio_id = %s AND order_id = %s AND execution_id = %s
+            """,
+            (seeded_portfolio, args["order_id"], args["execution_id"]),
+        )
+        assert cur.fetchone() == (1.0, None)
+
+
+def test_concurrent_conflicting_venue_enrichment_has_no_last_write_wins(
+    repo, seeded_portfolio
+):
+    args = {
+        "portfolio_id": seeded_portfolio,
+        "order_id": "ord-venue-concurrent",
+        "execution_id": "exec-venue-concurrent",
+        "side": "buy",
+        "quantity": 1.0,
+        "price": 10_000.0,
+        "executed_at": _now(),
+    }
+    repo.insert_ledger_trade(**args)
+    barrier = Barrier(2)
+
+    def enrich(execution_venue: str):
+        worker_repo = PostgresPortfolioRepository(repo._config)
+        barrier.wait()
+        try:
+            entry, created = worker_repo.insert_ledger_trade(
+                portfolio_id=seeded_portfolio,
+                order_id="ord-venue-concurrent",
+                execution_id="exec-venue-concurrent",
+                side="buy",
+                quantity=1.0,
+                price=10_000.0,
+                executed_at=args["executed_at"],
+                execution_venue=execution_venue,
+            )
+            return ("ok", created, entry.execution_venue)
+        except LedgerTradeConflictError:
+            return ("conflict", False, None)
+        finally:
+            worker_repo.close()
+
+    with ThreadPoolExecutor(max_workers=2) as executor:
+        results = list(executor.map(enrich, ("KRX", "NXT")))
+
+    assert sorted(result[0] for result in results) == ["conflict", "ok"]
+    winner = next(result[2] for result in results if result[0] == "ok")
+    assert winner in {"KRX", "NXT"}
+    with repo._connect().cursor() as cur:
+        cur.execute(
+            """
+            SELECT COUNT(*), MIN(execution_venue), MIN(order_venue)
+            FROM portfolio_ledger
+            WHERE portfolio_id = %s AND order_id = %s AND execution_id = %s
+            """,
+            (seeded_portfolio, args["order_id"], args["execution_id"]),
+        )
+        assert cur.fetchone() == (1, winner, None)
+
+
 def test_negative_balance_allowed(repo, seeded_portfolio):
     """REQ-037 AC-3 + OQ-3: oversell produces negative asset_quantity without rejection."""
     entry, created = repo.insert_ledger_trade(
diff --git a/tests/test_v1_portfolios_ledger.py b/tests/test_v1_portfolios_ledger.py
index e3c73b2..f5548fa 100644
--- a/tests/test_v1_portfolios_ledger.py
+++ b/tests/test_v1_portfolios_ledger.py
@@ -147,6 +147,97 @@ def test_ledger_trade_duplicate_same_payload() -> None:
     assert resp.json()["status"] == "duplicate"
 
 
+def test_ledger_trade_round_trips_and_forwards_venue_provenance() -> None:
+    settings = _make_settings()
+    repo = _make_service_repo(
+        trade=_make_trade(execution_venue="NXT", order_venue="SOR")
+    )
+    with _with_repo(repo):
+        client = _make_client(settings)
+        resp = client.post(
+            _NEW_PATH,
+            json=_trade_payload(execution_venue="NXT", order_venue="SOR"),
+            headers={"Authorization": "Bearer svc-token"},
+        )
+
+    assert resp.status_code == 201
+    assert resp.json()["execution_venue"] == "NXT"
+    assert resp.json()["order_venue"] == "SOR"
+    assert repo.insert_ledger_trade.call_args.kwargs["execution_venue"] == "NXT"
+    assert repo.insert_ledger_trade.call_args.kwargs["order_venue"] == "SOR"
+
+
+def test_ledger_trade_allows_unknown_actual_venue_with_sor_route() -> None:
+    settings = _make_settings()
+    repo = _make_service_repo(trade=_make_trade(execution_venue=None, order_venue="SOR"))
+    with _with_repo(repo):
+        client = _make_client(settings)
+        resp = client.post(
+            _NEW_PATH,
+            json=_trade_payload(execution_venue=None, order_venue="SOR"),
+            headers={"Authorization": "Bearer svc-token"},
+        )
+
+    assert resp.status_code == 201
+    assert resp.json()["execution_venue"] is None
+    assert resp.json()["order_venue"] == "SOR"
+
+
+def test_ledger_trade_rejects_sor_as_execution_venue() -> None:
+    settings = _make_settings()
+    repo = _make_service_repo()
+    with _with_repo(repo):
+        client = _make_client(settings)
+        resp = client.post(
+            _NEW_PATH,
+            json=_trade_payload(execution_venue="SOR", order_venue="SOR"),
+            headers={"Authorization": "Bearer svc-token"},
+        )
+
+    assert resp.status_code == 422
+    repo.insert_ledger_trade.assert_not_called()
+
+
+def test_ledger_trade_rejects_unknown_request_fields() -> None:
+    settings = _make_settings()
+    repo = _make_service_repo()
+    with _with_repo(repo):
+        client = _make_client(settings)
+        resp = client.post(
+            _NEW_PATH,
+            json=_trade_payload(broker_ordered_at="2026-05-01T09:59:59+09:00"),
+            headers={"Authorization": "Bearer svc-token"},
+        )
+
+    assert resp.status_code == 422
+    repo.insert_ledger_trade.assert_not_called()
+
+
+def test_ledger_trade_openapi_exposes_nullable_venue_enums() -> None:
+    settings = _make_settings()
+    repo = _make_service_repo()
+    with _with_repo(repo):
+        client = _make_client(settings)
+        response = client.get("/openapi.json")
+
+    assert response.status_code == 200
+    properties = response.json()["components"]["schemas"]["LedgerTradeRequest"][
+        "properties"
+    ]
+    execution_options = properties["execution_venue"]["anyOf"]
+    order_options = properties["order_venue"]["anyOf"]
+    assert {tuple(option.get("enum", ())) for option in execution_options} == {
+        (),
+        ("KRX", "NXT"),
+    }
+    assert {tuple(option.get("enum", ())) for option in order_options} == {
+        (),
+        ("KRX", "NXT", "SOR"),
+    }
+    assert {option.get("type") for option in execution_options} == {"string", "null"}
+    assert {option.get("type") for option in order_options} == {"string", "null"}
+
+
 # ---------------------------------------------------------------------------
 # AC-3: same key + different payload → 409
 # ---------------------------------------------------------------------------
diff --git a/tests/test_v1_portfolios_manual_ledger.py b/tests/test_v1_portfolios_manual_ledger.py
index 03af9f0..a38f2f4 100644
--- a/tests/test_v1_portfolios_manual_ledger.py
+++ b/tests/test_v1_portfolios_manual_ledger.py
@@ -1030,6 +1030,8 @@ def test_unified_ledger_includes_corporate_action_fields() -> None:
         "evidence_ref": "notice://ca-7",
         "actor_user_id": _USER_ID,
         "recorded_at": "2026-09-02T00:00:00Z",
+        "execution_venue": None,
+        "order_venue": None,
     }
 
 
@@ -1094,6 +1096,7 @@ def test_unified_ledger_paginates_mixed_sources_and_hides_side() -> None:
         LedgerEntry(
             ledger_entry_id=99, portfolio_id=_PORTFOLIO_ID, side="buy", quantity=2, price=10, source="broker",
             recorded_at=datetime.now(UTC), cash_balance_after=900, asset_quantity_after=12,
+            execution_venue="NXT", order_venue="SOR",
         )
     )
     first = client.get(f"/v1/portfolios/{_PORTFOLIO_ID}/ledger?limit=1", headers=_auth())
@@ -1101,6 +1104,8 @@ def test_unified_ledger_paginates_mixed_sources_and_hides_side() -> None:
     first_item = first.json()["items"][0]
     assert first_item["source"] == "broker"
     assert first_item["action"] == "BUY"
+    assert first_item["execution_venue"] == "NXT"
+    assert first_item["order_venue"] == "SOR"
     assert "side" not in first_item
     assert first.json()["next_cursor"]
     second = client.get(