diff --git a/CHANGELOG.md b/CHANGELOG.md
index 55a70e6..3edbb33 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,26 @@
 
 All notable changes to kalshi-sdk will be documented in this file.
 
+## 22.8.0 — 2026-11-04
+
+Reconciles nightly spec drift (#569) against OpenAPI 3.36.0 and the latest
+Klear (SCM) spec. Additive only. No breaking changes.
+
+### Added
+
+- Optional **`netting_enabled`** (`bool | None`) on `MarketPosition`. Spec
+  3.36.0 marks it required; the SDK keeps it optional (contract exclusion
+  `server_omits_despite_required`) so payloads omitting the key still parse.
+  (Closes #569).
+- Optional **`settlement_start_ts` / `settlement_end_ts`** (RFC3339
+  `datetime` or `str`) on Klear `margin.obligation_history` /
+  `obligation_history_all` (sync and async). Inclusive bounds on settlement
+  time; omitted keys are not sent.
+- Optional **`start_ts` / `end_ts`** (RFC3339 `datetime` or `str`) on Klear
+  `margin.settlement_balance_history` / `settlement_balance_history_all`
+  (sync and async). Inclusive bounds on entry creation time; omitted keys
+  are not sent.
+
 ## 22.7.0 — 2026-11-03
 
 Reconciles nightly spec drift (#567) against the latest perps OpenAPI /
diff --git a/docs/perps.md b/docs/perps.md
index a5b044c..af7a98b 100644
--- a/docs/perps.md
+++ b/docs/perps.md
@@ -340,7 +340,13 @@ Credentials can also come from the environment via `KlearClient.from_env()` (rea
 `KALSHI_KLEAR_ADMIN_USER_ID` / `KALSHI_KLEAR_ACCESS_TOKEN`).
 
 `klear.margin.active_obligations()` returns all currently-active settlement
-obligations. `klear.margin.settlement_estimate_by_asset_class()` returns
+obligations. `klear.margin.obligation_history()` / `obligation_history_all()`
+page historical obligations; optional `settlement_start_ts` /
+`settlement_end_ts` (RFC3339 `datetime` or `str`) bound settlement time.
+`klear.margin.settlement_balance_history()` /
+`settlement_balance_history_all()` page settlement-buffer history; optional
+`start_ts` / `end_ts` bound entry creation time. Omit a bound to leave it
+unfiltered. `klear.margin.settlement_estimate_by_asset_class()` returns
 next-settlement estimates keyed by asset class. (The singular
 `active_obligation()` / `settlement_estimate()` endpoints were removed upstream
 in the v11.0.0 reconcile.)
diff --git a/docs/resources/portfolio.md b/docs/resources/portfolio.md
index 21ee53b..7eb1d3e 100644
--- a/docs/resources/portfolio.md
+++ b/docs/resources/portfolio.md
@@ -300,7 +300,9 @@ are unaffected; constructors/fixtures must pass it.
 wire-format aliases — on the wire you see `total_traded_dollars`,
 `market_exposure_dollars`, `realized_pnl_dollars`, `fees_paid_dollars`,
 `position_fp`. The SDK normalizes to short names returning `Decimal`.
-`realized_pnl` is signed.
+`realized_pnl` is signed. Optional `netting_enabled` (`bool | None`) reports
+whether netting applies to the position's event (`None` when the server
+omits the key).
 
 ## Reference
 
diff --git a/kalshi/__init__.py b/kalshi/__init__.py
index 80e15d1..7e2c0a8 100644
--- a/kalshi/__init__.py
+++ b/kalshi/__init__.py
@@ -503,4 +503,4 @@
     "Withdrawal",
 ]
 
-__version__ = "22.7.0"
+__version__ = "22.8.0"
diff --git a/kalshi/models/portfolio.py b/kalshi/models/portfolio.py
index 649b51b..00fae68 100644
--- a/kalshi/models/portfolio.py
+++ b/kalshi/models/portfolio.py
@@ -104,6 +104,10 @@ class MarketPosition(BaseModel):
         validation_alias=AliasChoices("fees_paid_dollars", "fees_paid"),
     )
     last_updated_ts: AwareDatetime
+    # Spec 3.36.0 marks netting_enabled required. Kept optional (None when
+    # the key is absent) so payloads and fixtures from before the field
+    # still validate. See EXCLUSIONS.
+    netting_enabled: bool | None = None
 
     model_config = {"extra": "allow", "populate_by_name": True}
 
diff --git a/kalshi/perps/klear/resources/margin.py b/kalshi/perps/klear/resources/margin.py
index 035b4f1..af7cbc5 100644
--- a/kalshi/perps/klear/resources/margin.py
+++ b/kalshi/perps/klear/resources/margin.py
@@ -8,7 +8,9 @@
 - ``active_obligations`` — ``GET /margin/active_obligations``: all currently-active
   obligations.
 - ``obligation_history`` / ``obligation_history_all`` — ``GET
-  /margin/obligation_history``: cursor-paginated (limit max 100).
+  /margin/obligation_history``: cursor-paginated (limit max 100);
+  optional ``settlement_start_ts`` / ``settlement_end_ts`` (RFC3339) bound
+  settlement time.
 - ``settlement_details`` / ``settlement_details_all``,
   ``maintenance_margin_details`` / ``maintenance_margin_details_all``,
   ``funding_payments`` / ``funding_payments_all``,
@@ -20,7 +22,8 @@
 - ``settlement_balance`` — ``GET /margin/settlement_balance``.
 - ``guaranty_fund_balance`` — ``GET /margin/guaranty_fund_balance``.
 - ``settlement_balance_history`` / ``settlement_balance_history_all`` — ``GET
-  /margin/settlement_balance_history``: cursor-paginated (limit max 500).
+  /margin/settlement_balance_history``: cursor-paginated (limit max 500);
+  optional ``start_ts`` / ``end_ts`` (RFC3339) bound entry creation time.
 - ``withdraw_settlement_balance`` — ``POST /margin/settlement_balance_withdrawal``:
   ``WithdrawSettlementBalanceRequest`` body; NOT retried (POST).
 - ``settlement_balance_withdrawal`` — ``GET /margin/settlement_balance_withdrawal``:
@@ -117,6 +120,21 @@ def _validate_date_range(start_date: str, end_date: str) -> None:
         raise ValueError(f"end_date ({end_date}) must be on or after start_date ({start_date})")
 
 
+def _rfc3339(value: datetime.datetime | str | None) -> str | None:
+    """Coerce a ``datetime`` to RFC3339; pass strings through. ``None`` stays ``None``.
+
+    Naive datetimes (no ``tzinfo``) are assumed UTC. Spec requires RFC3339,
+    which mandates a timezone offset. Strings are forwarded unchanged.
+    """
+    if value is None:
+        return None
+    if isinstance(value, datetime.datetime):
+        if value.tzinfo is None:
+            value = value.replace(tzinfo=datetime.UTC)
+        return value.isoformat()
+    return value
+
+
 class MarginResource(KlearSyncResource):
     """Sync Klear (SCM) margin API — obligations, estimates, balances, groups."""
 
@@ -148,10 +166,21 @@ def obligation_history(
         *,
         limit: int | None = None,
         cursor: str | None = None,
+        settlement_start_ts: datetime.datetime | str | None = None,
+        settlement_end_ts: datetime.datetime | str | None = None,
         extra_headers: dict[str, str] | None = None,
     ) -> Page[ObligationEntry]:
-        """``GET /margin/obligation_history`` — one cursor-paginated page (limit max 100)."""
-        params = _params(limit=_validate_limit(limit, hi=100), cursor=cursor)
+        """``GET /margin/obligation_history`` — one cursor-paginated page (limit max 100).
+
+        ``settlement_start_ts`` / ``settlement_end_ts`` are optional RFC3339
+        bounds on settlement time (``datetime`` or string; omitted when ``None``).
+        """
+        params = _params(
+            limit=_validate_limit(limit, hi=100),
+            cursor=cursor,
+            settlement_start_ts=_rfc3339(settlement_start_ts),
+            settlement_end_ts=_rfc3339(settlement_end_ts),
+        )
         return self._list(
             "/margin/obligation_history",
             ObligationEntry,
@@ -166,11 +195,22 @@ def obligation_history_all(
         *,
         limit: int | None = None,
         max_pages: int | None = None,
+        settlement_start_ts: datetime.datetime | str | None = None,
+        settlement_end_ts: datetime.datetime | str | None = None,
         extra_headers: dict[str, str] | None = None,
     ) -> Iterator[ObligationEntry]:
-        """Auto-paginate obligation history, yielding each ``ObligationEntry``."""
+        """Auto-paginate obligation history, yielding each ``ObligationEntry``.
+
+        ``settlement_start_ts`` / ``settlement_end_ts`` are optional RFC3339
+        bounds on settlement time (``datetime`` or string; omitted when ``None``).
+        """
         _validate_max_pages(max_pages)
-        params = _params(limit=_validate_limit(limit, hi=100), cursor=None)
+        params = _params(
+            limit=_validate_limit(limit, hi=100),
+            cursor=None,
+            settlement_start_ts=_rfc3339(settlement_start_ts),
+            settlement_end_ts=_rfc3339(settlement_end_ts),
+        )
         return self._list_all(
             "/margin/obligation_history",
             ObligationEntry,
@@ -388,10 +428,21 @@ def settlement_balance_history(
         *,
         limit: int | None = None,
         cursor: str | None = None,
+        start_ts: datetime.datetime | str | None = None,
+        end_ts: datetime.datetime | str | None = None,
         extra_headers: dict[str, str] | None = None,
     ) -> Page[SettlementBalanceHistoryEntry]:
-        """``GET /margin/settlement_balance_history`` — one page (limit max 500)."""
-        params = _params(limit=_validate_limit(limit, hi=500), cursor=cursor)
+        """``GET /margin/settlement_balance_history`` — one page (limit max 500).
+
+        ``start_ts`` / ``end_ts`` are optional RFC3339 bounds on entry
+        creation time (``datetime`` or string; omitted when ``None``).
+        """
+        params = _params(
+            limit=_validate_limit(limit, hi=500),
+            cursor=cursor,
+            start_ts=_rfc3339(start_ts),
+            end_ts=_rfc3339(end_ts),
+        )
         return self._list(
             "/margin/settlement_balance_history",
             SettlementBalanceHistoryEntry,
@@ -406,11 +457,22 @@ def settlement_balance_history_all(
         *,
         limit: int | None = None,
         max_pages: int | None = None,
+        start_ts: datetime.datetime | str | None = None,
+        end_ts: datetime.datetime | str | None = None,
         extra_headers: dict[str, str] | None = None,
     ) -> Iterator[SettlementBalanceHistoryEntry]:
-        """Auto-paginate settlement-balance history, yielding each entry."""
+        """Auto-paginate settlement-balance history, yielding each entry.
+
+        ``start_ts`` / ``end_ts`` are optional RFC3339 bounds on entry
+        creation time (``datetime`` or string; omitted when ``None``).
+        """
         _validate_max_pages(max_pages)
-        params = _params(limit=_validate_limit(limit, hi=500), cursor=None)
+        params = _params(
+            limit=_validate_limit(limit, hi=500),
+            cursor=None,
+            start_ts=_rfc3339(start_ts),
+            end_ts=_rfc3339(end_ts),
+        )
         return self._list_all(
             "/margin/settlement_balance_history",
             SettlementBalanceHistoryEntry,
@@ -759,10 +821,17 @@ async def obligation_history(
         *,
         limit: int | None = None,
         cursor: str | None = None,
+        settlement_start_ts: datetime.datetime | str | None = None,
+        settlement_end_ts: datetime.datetime | str | None = None,
         extra_headers: dict[str, str] | None = None,
     ) -> Page[ObligationEntry]:
         """Async :meth:`MarginResource.obligation_history`."""
-        params = _params(limit=_validate_limit(limit, hi=100), cursor=cursor)
+        params = _params(
+            limit=_validate_limit(limit, hi=100),
+            cursor=cursor,
+            settlement_start_ts=_rfc3339(settlement_start_ts),
+            settlement_end_ts=_rfc3339(settlement_end_ts),
+        )
         return await self._list(
             "/margin/obligation_history",
             ObligationEntry,
@@ -777,11 +846,18 @@ def obligation_history_all(
         *,
         limit: int | None = None,
         max_pages: int | None = None,
+        settlement_start_ts: datetime.datetime | str | None = None,
+        settlement_end_ts: datetime.datetime | str | None = None,
         extra_headers: dict[str, str] | None = None,
     ) -> AsyncIterator[ObligationEntry]:
         """Returns an async iterator over obligation history — use ``async for``."""
         _validate_max_pages(max_pages)
-        params = _params(limit=_validate_limit(limit, hi=100), cursor=None)
+        params = _params(
+            limit=_validate_limit(limit, hi=100),
+            cursor=None,
+            settlement_start_ts=_rfc3339(settlement_start_ts),
+            settlement_end_ts=_rfc3339(settlement_end_ts),
+        )
         return self._list_all(
             "/margin/obligation_history",
             ObligationEntry,
@@ -992,10 +1068,17 @@ async def settlement_balance_history(
         *,
         limit: int | None = None,
         cursor: str | None = None,
+        start_ts: datetime.datetime | str | None = None,
+        end_ts: datetime.datetime | str | None = None,
         extra_headers: dict[str, str] | None = None,
     ) -> Page[SettlementBalanceHistoryEntry]:
         """Async :meth:`MarginResource.settlement_balance_history`."""
-        params = _params(limit=_validate_limit(limit, hi=500), cursor=cursor)
+        params = _params(
+            limit=_validate_limit(limit, hi=500),
+            cursor=cursor,
+            start_ts=_rfc3339(start_ts),
+            end_ts=_rfc3339(end_ts),
+        )
         return await self._list(
             "/margin/settlement_balance_history",
             SettlementBalanceHistoryEntry,
@@ -1010,11 +1093,18 @@ def settlement_balance_history_all(
         *,
         limit: int | None = None,
         max_pages: int | None = None,
+        start_ts: datetime.datetime | str | None = None,
+        end_ts: datetime.datetime | str | None = None,
         extra_headers: dict[str, str] | None = None,
     ) -> AsyncIterator[SettlementBalanceHistoryEntry]:
         """Returns an async iterator over settlement-balance history — use ``async for``."""
         _validate_max_pages(max_pages)
-        params = _params(limit=_validate_limit(limit, hi=500), cursor=None)
+        params = _params(
+            limit=_validate_limit(limit, hi=500),
+            cursor=None,
+            start_ts=_rfc3339(start_ts),
+            end_ts=_rfc3339(end_ts),
+        )
         return self._list_all(
             "/margin/settlement_balance_history",
             SettlementBalanceHistoryEntry,
diff --git a/pyproject.toml b/pyproject.toml
index 496cb40..dd9111c 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [project]
 name = "kalshi-sdk"
-version = "22.7.0"
+version = "22.8.0"
 description = "A professional Python SDK for the Kalshi prediction markets and Perps (margin) APIs"
 readme = "README.md"
 license = { text = "MIT" }
diff --git a/specs/asyncapi.yaml b/specs/asyncapi.yaml
index 9a23505..005d60c 100644
--- a/specs/asyncapi.yaml
+++ b/specs/asyncapi.yaml
@@ -4426,7 +4426,8 @@ components:
                 Identifier of the RFQ batch this RFQ is a child of. Omitted for an
                 RFQ outside a batch. A child can be quoted like a single RFQ, with
                 these differences: a quote counts only for 30 seconds after it was
-                sent, and resending an unchanged bid keeps its time priority;
+                sent, and resending an unchanged bid keeps its time priority only
+                within those 30 seconds;
                 nothing executes until every winning maker of the batch has
                 confirmed, so a confirmed quote can still close without a fill;
                 an accepted quote can't be cancelled, and not confirming it lapses
@@ -4569,7 +4570,7 @@ components:
           properties:
             quote_id:
               type: string
-              description: Unique identifier for the quote
+              description: Unique identifier of the quote that executes. It can differ from the quote the RFQ creator named
             rfq_id:
               type: string
               description: Identifier of the RFQ this quote is for
diff --git a/specs/openapi.yaml b/specs/openapi.yaml
index 432c33b..6a77632 100644
--- a/specs/openapi.yaml
+++ b/specs/openapi.yaml
@@ -1,7 +1,7 @@
 openapi: 3.0.0
 info:
   title: Kalshi Trade API Manual Endpoints
-  version: 3.35.0
+  version: 3.36.0
   description: Manually defined OpenAPI spec for endpoints being migrated to spec-first approach
 
 servers:
@@ -2564,7 +2564,10 @@ paths:
     put:
       operationId: AcceptRFQQuote
       summary: Accept RFQ Quote
-      description: ' Endpoint for accepting a quote scoped to its RFQ. This will require the quoter to confirm.'
+      description: >-
+        Endpoint for accepting a quote scoped to its RFQ. This will require the quoter to confirm.
+        The quote that fills can be another maker's quote at the same price; see
+        [RFQs](/getting_started/rfqs#flow).
       tags:
         - communications
       security:
@@ -3054,8 +3057,11 @@ paths:
       operationId: GetQuotes
       summary: Get Quotes
       description: >-
-        List quotes. The rfq_id filter requires an RFQ UUID. Pass pagination
-        cursors back unchanged; malformed RFQ IDs or cursors return HTTP 400.
+        List quotes. The rfq_id filter requires an RFQ UUID. With rfq_id, quotes
+        are sorted on the RFQ's main side (no for a target-cost RFQ, yes
+        otherwise): the best price first, then the earliest place in line at that
+        price. Pass pagination cursors back unchanged; malformed RFQ IDs or
+        cursors return HTTP 400.
       tags:
         - communications
       security:
@@ -3262,7 +3268,7 @@ paths:
       operationId: AcceptQuote
       summary: Accept Quote
       deprecated: true
-      description: 'DEPRECATED: Use PUT /communications/rfqs/{rfq_id}/quotes/{quote_id}/accept instead. Endpoint for accepting a quote. This will require the quoter to confirm.'
+      description: 'DEPRECATED: Use PUT /communications/rfqs/{rfq_id}/quotes/{quote_id}/accept instead.'
       x-mint:
         content: |
           <Warning>
@@ -7815,6 +7821,7 @@ components:
         - realized_pnl_dollars
         - fees_paid_dollars
         - last_updated_ts
+        - netting_enabled
       properties:
         ticker:
           type: string
@@ -7841,6 +7848,9 @@ components:
           type: string
           format: date-time
           description: Last time the position is updated
+        netting_enabled:
+          type: boolean
+          description: Whether netting applies to this position's event. Set at the subaccount's first order in the event.
 
     EventPosition:
       type: object
diff --git a/specs/perps_scm_openapi.yaml b/specs/perps_scm_openapi.yaml
index cecab03..79f57bd 100644
--- a/specs/perps_scm_openapi.yaml
+++ b/specs/perps_scm_openapi.yaml
@@ -80,6 +80,8 @@ paths:
       parameters:
         - { name: limit, in: query, required: false, schema: { type: integer, default: 20, maximum: 100 }, description: Number of results per page. }
         - { name: cursor, in: query, required: false, schema: { type: string }, description: Opaque cursor from a previous response to fetch the next page. }
+        - { name: settlement_start_ts, in: query, required: false, schema: { type: string, format: date-time }, description: Inclusive lower bound on settlement time. }
+        - { name: settlement_end_ts, in: query, required: false, schema: { type: string, format: date-time }, description: Inclusive upper bound on settlement time. }
       responses:
         '200':
           description: Successful response
@@ -425,6 +427,8 @@ paths:
       parameters:
         - { name: limit, in: query, required: false, schema: { type: integer, default: 100, maximum: 500 }, description: Number of results per page. }
         - { name: cursor, in: query, required: false, schema: { type: string }, description: Cursor from a previous response to fetch the next page. }
+        - { name: start_ts, in: query, required: false, schema: { type: string, format: date-time }, description: Inclusive lower bound on entry creation time. }
+        - { name: end_ts, in: query, required: false, schema: { type: string, format: date-time }, description: Inclusive upper bound on entry creation time. }
       responses:
         '200':
           description: Successful response
diff --git a/tests/_contract_support.py b/tests/_contract_support.py
index 5a14f31..f527040 100644
--- a/tests/_contract_support.py
+++ b/tests/_contract_support.py
@@ -1444,6 +1444,14 @@ class Exclusion:
         ),
         kind="server_omits_despite_required",
     ),
+    ("kalshi.models.portfolio.MarketPosition", "netting_enabled"): Exclusion(
+        reason=(
+            "spec 3.36.0 marks netting_enabled required; the SDK keeps it "
+            "optional (None when absent) so payloads and fixtures predating the "
+            "field still validate and the change ships as a minor release (22.8.0)."
+        ),
+        kind="server_omits_despite_required",
+    ),
     # --- server_omits_despite_required (#183, post-#172 nightly findings) ---
     # Fields the OpenAPI spec marks `required: true` but the live demo server
     # omits in practice. Each entry MUST cite a demo+prod observation in
diff --git a/tests/perps/klear/test_margin.py b/tests/perps/klear/test_margin.py
index 3820eeb..0f18f7c 100644
--- a/tests/perps/klear/test_margin.py
+++ b/tests/perps/klear/test_margin.py
@@ -19,6 +19,7 @@
 from __future__ import annotations
 
 import json
+from datetime import UTC, datetime
 from decimal import Decimal
 
 import httpx
@@ -512,6 +513,138 @@ async def test_async_all_paginates(self, auth_async_klear_client: AsyncKlearClie
         assert len(items) == 2
         await auth_async_klear_client.close()
 
+    @respx.mock
+    def test_settlement_window_sent_on_wire(self, auth_klear_client: KlearClient) -> None:
+        route = respx.get(f"{BASE}/margin/obligation_history").mock(
+            return_value=httpx.Response(
+                200, json={"obligations": [_obligation()], "cursor": ""}
+            )
+        )
+        auth_klear_client.margin.obligation_history(
+            settlement_start_ts="2026-01-01T00:00:00Z",
+            settlement_end_ts="2026-01-31T23:59:59Z",
+        )
+        params = route.calls[0].request.url.params
+        assert params["settlement_start_ts"] == "2026-01-01T00:00:00Z"
+        assert params["settlement_end_ts"] == "2026-01-31T23:59:59Z"
+        start = datetime(2026, 2, 1, tzinfo=UTC)
+        end = datetime(2026, 2, 28, tzinfo=UTC)
+        auth_klear_client.margin.obligation_history(
+            settlement_start_ts=start, settlement_end_ts=end
+        )
+        params = route.calls[1].request.url.params
+        assert params["settlement_start_ts"] == start.isoformat()
+        assert params["settlement_end_ts"] == end.isoformat()
+        auth_klear_client.close()
+
+    @respx.mock
+    def test_settlement_window_omitted_when_none(self, auth_klear_client: KlearClient) -> None:
+        route = respx.get(f"{BASE}/margin/obligation_history").mock(
+            return_value=httpx.Response(
+                200, json={"obligations": [_obligation()], "cursor": ""}
+            )
+        )
+        auth_klear_client.margin.obligation_history()
+        params = route.calls[0].request.url.params
+        assert "settlement_start_ts" not in params
+        assert "settlement_end_ts" not in params
+        auth_klear_client.close()
+
+    @respx.mock
+    def test_all_settlement_window_sent_on_wire(self, auth_klear_client: KlearClient) -> None:
+        route = respx.get(f"{BASE}/margin/obligation_history").mock(
+            return_value=httpx.Response(
+                200, json={"obligations": [_obligation()], "cursor": ""}
+            )
+        )
+        list(
+            auth_klear_client.margin.obligation_history_all(
+                settlement_start_ts="2026-01-01T00:00:00Z",
+                settlement_end_ts="2026-01-31T23:59:59Z",
+            )
+        )
+        params = route.calls[0].request.url.params
+        assert params["settlement_start_ts"] == "2026-01-01T00:00:00Z"
+        assert params["settlement_end_ts"] == "2026-01-31T23:59:59Z"
+        list(auth_klear_client.margin.obligation_history_all())
+        params = route.calls[1].request.url.params
+        assert "settlement_start_ts" not in params
+        assert "settlement_end_ts" not in params
+        auth_klear_client.close()
+
+    @respx.mock
+    async def test_async_settlement_window_sent_on_wire(
+        self, auth_async_klear_client: AsyncKlearClient
+    ) -> None:
+        route = respx.get(f"{BASE}/margin/obligation_history").mock(
+            return_value=httpx.Response(
+                200, json={"obligations": [_obligation()], "cursor": ""}
+            )
+        )
+        await auth_async_klear_client.margin.obligation_history(
+            settlement_start_ts="2026-01-01T00:00:00Z",
+            settlement_end_ts="2026-01-31T23:59:59Z",
+        )
+        params = route.calls[0].request.url.params
+        assert params["settlement_start_ts"] == "2026-01-01T00:00:00Z"
+        assert params["settlement_end_ts"] == "2026-01-31T23:59:59Z"
+        await auth_async_klear_client.margin.obligation_history()
+        params = route.calls[1].request.url.params
+        assert "settlement_start_ts" not in params
+        assert "settlement_end_ts" not in params
+        await auth_async_klear_client.close()
+
+    @respx.mock
+    async def test_async_all_settlement_window_sent_on_wire(
+        self, auth_async_klear_client: AsyncKlearClient
+    ) -> None:
+        route = respx.get(f"{BASE}/margin/obligation_history").mock(
+            return_value=httpx.Response(
+                200, json={"obligations": [_obligation()], "cursor": ""}
+            )
+        )
+        items = [
+            o
+            async for o in auth_async_klear_client.margin.obligation_history_all(
+                settlement_start_ts="2026-01-01T00:00:00Z",
+                settlement_end_ts="2026-01-31T23:59:59Z",
+            )
+        ]
+        assert len(items) == 1
+        params = route.calls[0].request.url.params
+        assert params["settlement_start_ts"] == "2026-01-01T00:00:00Z"
+        assert params["settlement_end_ts"] == "2026-01-31T23:59:59Z"
+        items = [o async for o in auth_async_klear_client.margin.obligation_history_all()]
+        assert len(items) == 1
+        params = route.calls[1].request.url.params
+        assert "settlement_start_ts" not in params
+        assert "settlement_end_ts" not in params
+        await auth_async_klear_client.close()
+
+    @respx.mock
+    def test_settlement_window_server_4xx_raises(self, auth_klear_client: KlearClient) -> None:
+        respx.get(f"{BASE}/margin/obligation_history").mock(
+            return_value=httpx.Response(400, json={"code": "bad", "message": "bad window"})
+        )
+        with pytest.raises(KalshiValidationError):
+            auth_klear_client.margin.obligation_history(
+                settlement_start_ts="2026-01-01T00:00:00Z"
+            )
+        auth_klear_client.close()
+
+    @respx.mock
+    async def test_async_settlement_window_server_4xx_raises(
+        self, auth_async_klear_client: AsyncKlearClient
+    ) -> None:
+        respx.get(f"{BASE}/margin/obligation_history").mock(
+            return_value=httpx.Response(400, json={"code": "bad", "message": "bad window"})
+        )
+        with pytest.raises(KalshiValidationError):
+            await auth_async_klear_client.margin.obligation_history(
+                settlement_end_ts="2026-01-31T23:59:59Z"
+            )
+        await auth_async_klear_client.close()
+
 
 # --------------------------------------------------------------------------- #
 # obligation detail pages (settlement / MM / funding)
@@ -915,6 +1048,136 @@ async def test_async_all_paginates(self, auth_async_klear_client: AsyncKlearClie
         assert len(items) == 2
         await auth_async_klear_client.close()
 
+    @respx.mock
+    def test_creation_window_sent_on_wire(self, auth_klear_client: KlearClient) -> None:
+        route = respx.get(f"{BASE}/margin/settlement_balance_history").mock(
+            return_value=httpx.Response(
+                200, json={"entries": [_balance_history_entry()], "cursor": ""}
+            )
+        )
+        auth_klear_client.margin.settlement_balance_history(
+            start_ts="2026-01-01T00:00:00Z",
+            end_ts="2026-01-31T23:59:59Z",
+        )
+        params = route.calls[0].request.url.params
+        assert params["start_ts"] == "2026-01-01T00:00:00Z"
+        assert params["end_ts"] == "2026-01-31T23:59:59Z"
+        start = datetime(2026, 2, 1, tzinfo=UTC)
+        end = datetime(2026, 2, 28, tzinfo=UTC)
+        auth_klear_client.margin.settlement_balance_history(start_ts=start, end_ts=end)
+        params = route.calls[1].request.url.params
+        assert params["start_ts"] == start.isoformat()
+        assert params["end_ts"] == end.isoformat()
+        auth_klear_client.close()
+
+    @respx.mock
+    def test_creation_window_omitted_when_none(self, auth_klear_client: KlearClient) -> None:
+        route = respx.get(f"{BASE}/margin/settlement_balance_history").mock(
+            return_value=httpx.Response(
+                200, json={"entries": [_balance_history_entry()], "cursor": ""}
+            )
+        )
+        auth_klear_client.margin.settlement_balance_history()
+        params = route.calls[0].request.url.params
+        assert "start_ts" not in params
+        assert "end_ts" not in params
+        auth_klear_client.close()
+
+    @respx.mock
+    def test_all_creation_window_sent_on_wire(self, auth_klear_client: KlearClient) -> None:
+        route = respx.get(f"{BASE}/margin/settlement_balance_history").mock(
+            return_value=httpx.Response(
+                200, json={"entries": [_balance_history_entry()], "cursor": ""}
+            )
+        )
+        list(
+            auth_klear_client.margin.settlement_balance_history_all(
+                start_ts="2026-01-01T00:00:00Z",
+                end_ts="2026-01-31T23:59:59Z",
+            )
+        )
+        params = route.calls[0].request.url.params
+        assert params["start_ts"] == "2026-01-01T00:00:00Z"
+        assert params["end_ts"] == "2026-01-31T23:59:59Z"
+        list(auth_klear_client.margin.settlement_balance_history_all())
+        params = route.calls[1].request.url.params
+        assert "start_ts" not in params
+        assert "end_ts" not in params
+        auth_klear_client.close()
+
+    @respx.mock
+    async def test_async_creation_window_sent_on_wire(
+        self, auth_async_klear_client: AsyncKlearClient
+    ) -> None:
+        route = respx.get(f"{BASE}/margin/settlement_balance_history").mock(
+            return_value=httpx.Response(
+                200, json={"entries": [_balance_history_entry()], "cursor": ""}
+            )
+        )
+        await auth_async_klear_client.margin.settlement_balance_history(
+            start_ts="2026-01-01T00:00:00Z",
+            end_ts="2026-01-31T23:59:59Z",
+        )
+        params = route.calls[0].request.url.params
+        assert params["start_ts"] == "2026-01-01T00:00:00Z"
+        assert params["end_ts"] == "2026-01-31T23:59:59Z"
+        await auth_async_klear_client.margin.settlement_balance_history()
+        params = route.calls[1].request.url.params
+        assert "start_ts" not in params
+        assert "end_ts" not in params
+        await auth_async_klear_client.close()
+
+    @respx.mock
+    async def test_async_all_creation_window_sent_on_wire(
+        self, auth_async_klear_client: AsyncKlearClient
+    ) -> None:
+        route = respx.get(f"{BASE}/margin/settlement_balance_history").mock(
+            return_value=httpx.Response(
+                200, json={"entries": [_balance_history_entry()], "cursor": ""}
+            )
+        )
+        items = [
+            e
+            async for e in auth_async_klear_client.margin.settlement_balance_history_all(
+                start_ts="2026-01-01T00:00:00Z",
+                end_ts="2026-01-31T23:59:59Z",
+            )
+        ]
+        assert len(items) == 1
+        params = route.calls[0].request.url.params
+        assert params["start_ts"] == "2026-01-01T00:00:00Z"
+        assert params["end_ts"] == "2026-01-31T23:59:59Z"
+        items = [
+            e async for e in auth_async_klear_client.margin.settlement_balance_history_all()
+        ]
+        assert len(items) == 1
+        params = route.calls[1].request.url.params
+        assert "start_ts" not in params
+        assert "end_ts" not in params
+        await auth_async_klear_client.close()
+
+    @respx.mock
+    def test_creation_window_server_4xx_raises(self, auth_klear_client: KlearClient) -> None:
+        respx.get(f"{BASE}/margin/settlement_balance_history").mock(
+            return_value=httpx.Response(400, json={"code": "bad", "message": "bad window"})
+        )
+        with pytest.raises(KalshiValidationError):
+            auth_klear_client.margin.settlement_balance_history(start_ts="2026-01-01T00:00:00Z")
+        auth_klear_client.close()
+
+    @respx.mock
+    async def test_async_creation_window_server_4xx_raises(
+        self, auth_async_klear_client: AsyncKlearClient
+    ) -> None:
+        respx.get(f"{BASE}/margin/settlement_balance_history").mock(
+            return_value=httpx.Response(400, json={"code": "bad", "message": "bad window"})
+        )
+        with pytest.raises(KalshiValidationError):
+            await auth_async_klear_client.margin.settlement_balance_history(
+                end_ts="2026-01-31T23:59:59Z"
+            )
+        await auth_async_klear_client.close()
+
 
 # --------------------------------------------------------------------------- #
 # withdraw_settlement_balance
diff --git a/tests/test_models.py b/tests/test_models.py
index 6e0e0b4..16cdeb4 100644
--- a/tests/test_models.py
+++ b/tests/test_models.py
@@ -20,7 +20,7 @@
     OrderGroup,
 )
 from kalshi.models.orders import Fill, Order
-from kalshi.models.portfolio import Settlement
+from kalshi.models.portfolio import MarketPosition, Settlement
 from kalshi.types import to_decimal
 from tests._model_fixtures import (
     candlestick_dict,
@@ -31,6 +31,7 @@
     get_order_group_response_dict,
     incentive_program_dict,
     market_dict,
+    market_position_dict,
     order_dict,
     settlement_dict,
     trade_dict,
@@ -567,6 +568,25 @@ def test_is_block_trade_missing_raises(self) -> None:
             Trade.model_validate(data)
 
 
+class TestMarketPositionNettingEnabled:
+    """Spec 3.36.0 marks ``netting_enabled`` required; SDK keeps it optional."""
+
+    def test_parses_netting_enabled(self) -> None:
+        assert (
+            MarketPosition.model_validate(market_position_dict(netting_enabled=True)).netting_enabled
+            is True
+        )
+        assert (
+            MarketPosition.model_validate(
+                market_position_dict(netting_enabled=False)
+            ).netting_enabled
+            is False
+        )
+
+    def test_parses_without_netting_enabled(self) -> None:
+        assert MarketPosition.model_validate(market_position_dict()).netting_enabled is None
+
+
 class TestIncentiveProgramV3180Fields:
     """v3.18.0 backfill (issue #160): 1 new optional field on ``IncentiveProgram``."""