diff --git a/api/shopping_models.py b/api/shopping_models.py
index 2b615d4..b07a191 100644
--- a/api/shopping_models.py
+++ b/api/shopping_models.py
@@ -6,7 +6,7 @@ from enum import Enum
 
 import ingredients
 import meals
-import persons
+from api.dtos import MemberRef
 import recipes
 import shopping
 from common import ApiModel, Field
@@ -61,7 +61,7 @@ class ShoppingListOut(ApiModel):
     # outward-only enum values: include "home" instead of an empty string
     store_name: Literal["woolworths", "coles", "home"]
     purchased_by_id: int
-    purchased_by: persons.Person | None = None
+    purchased_by: MemberRef | None = None
     # Make items required in the schema; callers must always send an array (possibly empty)
     items: List[ListIngredientItem] = Field(min_length=0, json_schema_extra={"minItems": 0})
 
@@ -120,11 +120,24 @@ def _to_shopping_list_out(sl: shopping.ShoppingList) -> ShoppingListOut:
     else:
         # Remaining enum values are 'woolworths' or 'coles'
         outward_store = cast(Literal["woolworths", "coles"], sl.store_name.value)
+    # Map purchased_by if present: expect ShoppingList.purchased_by to carry display_name if available
+    mref = None
+    if sl.purchased_by is not None:
+        try:
+            # sl.purchased_by may be a lightweight object with id/name
+            pid = getattr(sl.purchased_by, "id", None)
+            pname = getattr(sl.purchased_by, "name", None) or getattr(
+                sl.purchased_by, "display_name", None
+            )
+            if isinstance(pid, int) and pname:
+                mref = MemberRef(id=pid, display_name=pname)
+        except Exception:
+            mref = None
     return ShoppingListOut(
         id=sl.id,
         created_date=sl.created_date,
         store_name=outward_store,
         purchased_by_id=sl.purchased_by_id,
-        purchased_by=sl.purchased_by,
+        purchased_by=mref,
         items=[_to_ingredient_item(i) for i in sl.items],
     )
diff --git a/backend-spec.md b/backend-spec.md
index 2a4d207..708eac6 100644
--- a/backend-spec.md
+++ b/backend-spec.md
@@ -274,6 +274,7 @@ Repositories accept `household_id` and filter by it across `meals`, `recipes`, a
 Status summary:
 - Implemented: JWT auth v2 with refresh cookie; household domains and membership; invitations; full household scoping across recipes/meals/shopping; OpenAPI augmentation with bearerAuth and 403; RFC7807 preserved; tests green.
 - DTO alignment: Meals use MemberRef { id, displayName } (no Person in outward schema). MemberRef consolidated in `api/dtos.py`. Shopping DTOs/mappers consolidated in `api/shopping_models.py`.
+ - DTO alignment (v2): Meals use MemberRef; Recipes include `createdById` and `createdBy` (MemberRef); Shopping `purchasedBy` is now a MemberRef on outward lists.
 - Security: Password hashing now prefers Argon2 for new accounts with PBKDF2 verification fallback.
 - New: Household members listing `GET /api/v1/households/{householdSlug}/members` returning [{ id, displayName, role }].
 - Preserved: camelCase responses, `Page<T>` semantics, `Location` headers on create, shopping storeName normalization ("home").
@@ -286,7 +287,7 @@ Remaining work (prioritized cleanup to final state):
   - Replace internal usages with `user_id`/`MemberRef` where outward, and update repository DDL to stop referencing `Person`.
   - Remove `api.deps.cookie_person` once no tests or code depend on it.
 2. Recipes outward schema: DONE for `createdById`/`createdBy` (MemberRef). Remaining: add `hiddenBy` (MemberRef) when hide flows are wired to users.
-3. Shopping outward DTOs: change `ShoppingListOut.purchasedBy` from `Person` to `MemberRef` and adjust mapping code in `api/shopping_models.py`; ensure OpenAPI reflects the new shape. Consider exposing only `purchasedById` initially if membership lookup isn’t available.
+3. Shopping outward DTOs: DONE — `ShoppingListOut.purchasedBy` is a MemberRef; mapping added. Ensure clients shift to `displayName`.
 4. Delete or port legacy v1 test modules that are currently skipped (`tests/test_main.py`, `tests/test_v1.py`). Either migrate assertions to v2 routes or remove them so the full test run has no skips. Then remove the last vestiges of v1-only helpers.
 5. Database polish:
   - Add composite indices like `(household_id, id)` where pagination benefits (e.g., Recipe, Meal, ShoppingListItem).
diff --git a/openapi.json b/openapi.json
index 61b061c..719bab8 100644
--- a/openapi.json
+++ b/openapi.json
@@ -2748,7 +2748,7 @@
           "purchasedBy": {
             "anyOf": [
               {
-                "$ref": "#/components/schemas/Person"
+                "$ref": "#/components/schemas/MemberRef"
               },
               {
                 "type": "null"
diff --git a/shopping/repository.py b/shopping/repository.py
index aa7cefa..7588b9e 100644
--- a/shopping/repository.py
+++ b/shopping/repository.py
@@ -482,14 +482,30 @@ async def load_shopping_list_scoped(conn, id: int, household_id: int) -> Optiona
     shopping_list: Optional[ShoppingList] = None
     async with conn.execute(
         f"""
-        SELECT {",".join(ShoppingList.KEYS)} FROM ShoppingList
+        SELECT {",".join(ShoppingList.KEYS)}, (
+            SELECT display_name FROM User u WHERE u.id = ShoppingList.purchased_by_id
+        ) as purchased_by_name
+        FROM ShoppingList
         WHERE id = ? AND household_id = ?
         LIMIT 1
     """,
         (id, household_id),
     ) as cursor:
         async for row in cursor:
-            shopping_list = ShoppingList(**{k: v for k, v in zip(ShoppingList.KEYS, row)})
+            base = {k: v for k, v in zip(ShoppingList.KEYS, row[: len(ShoppingList.KEYS)])}
+            shopping_list = ShoppingList(**base)
+            # Attach a lightweight purchased_by with display_name if available
+            try:
+                display_name = row[len(ShoppingList.KEYS)]
+                if display_name and shopping_list.purchased_by_id is not None:
+                    # Reuse legacy Person model for internal typing until users fully replace persons
+                    from persons.models import Person
+
+                    shopping_list.purchased_by = Person(
+                        id=int(shopping_list.purchased_by_id), name=display_name
+                    )
+            except Exception:
+                pass
             break
 
     if shopping_list:
diff --git a/tests/test_shopping_list_by_id_v2.py b/tests/test_shopping_list_by_id_v2.py
index caeb55a..a1d3965 100644
--- a/tests/test_shopping_list_by_id_v2.py
+++ b/tests/test_shopping_list_by_id_v2.py
@@ -107,6 +107,11 @@ class TestShoppingListByIdV2(unittest.IsolatedAsyncioTestCase):
         body = resp_ok.json()
         assert body["list"]["id"] == self.h1_list_id
         assert len(body["list"]["items"]) == 1
+        # purchasedBy is included as MemberRef
+        assert "purchasedBy" in body["list"]
+        pb = body["list"]["purchasedBy"]
+        assert isinstance(pb, dict)
+        assert "id" in pb and "displayName" in pb
 
         # Cross-household should 404
         resp_404 = self.client.get(