From 6db44e8aac20ee191912e81b638b640f3adcea20 Mon Sep 17 00:00:00 2001
From: Lenz Weber-Tronic <lorenz.weber-tronic@apollographql.com>
Date: Wed, 18 Jun 2025 17:17:56 +0200
Subject: [PATCH 01/10] wip

---
 src/core/ObservableQuery.ts   | 49 +++++++++++++++++------------------
 src/core/watchQueryOptions.ts | 20 ++++++++++----
 2 files changed, 39 insertions(+), 30 deletions(-)

diff --git a/src/core/ObservableQuery.ts b/src/core/ObservableQuery.ts
index 929bfbbb41e..fedc16f6657 100644
--- a/src/core/ObservableQuery.ts
+++ b/src/core/ObservableQuery.ts
@@ -708,29 +708,30 @@ Did you mean to call refetch(variables) instead of refetch({ variables })?`,
   public fetchMore<
     TFetchData = TData,
     TFetchVars extends OperationVariables = TVariables,
-  >(
-    fetchMoreOptions: FetchMoreQueryOptions<TFetchVars, TFetchData> & {
-      updateQuery?: (
-        previousQueryResult: Unmasked<TData>,
-        options: {
-          fetchMoreResult: Unmasked<TFetchData>;
-          variables: TFetchVars;
-        }
-      ) => Unmasked<TData>;
-    }
-  ): Promise<QueryResult<TFetchData>> {
+  >({
+    query,
+    variables,
+    context,
+    errorPolicy,
+    fetchPolicy,
+    updateQuery,
+  }: FetchMoreQueryOptions<TFetchVars, TFetchData> & {
+    updateQuery?: (
+      previousQueryResult: Unmasked<TData>,
+      options: {
+        fetchMoreResult: Unmasked<TData>;
+        variables: NoInfer<TVariables>;
+      }
+    ) => Unmasked<TData>;
+  }): Promise<QueryResult<TFetchData>> {
     const combinedOptions = {
-      ...(fetchMoreOptions.query ? fetchMoreOptions : (
-        {
-          ...this.options,
-          query: this.options.query,
-          ...fetchMoreOptions,
-          variables: {
-            ...this.variables,
-            ...fetchMoreOptions.variables,
-          },
-        }
-      )),
+      ...compact(this.options, {
+        query,
+        variables,
+        context,
+        errorPolicy,
+        fetchPolicy,
+      }),
       // The fetchMore request goes immediately to the network and does
       // not automatically write its result to the cache (hence no-cache
       // instead of network-only), because we allow the caller of
@@ -748,13 +749,12 @@ Did you mean to call refetch(variables) instead of refetch({ variables })?`,
     // as well as the document passed in `fetchMoreOptions` to ensure the cache
     // uses the most up-to-date document which may rely on runtime conditionals.
     this.lastQuery =
-      fetchMoreOptions.query ?
+      query ?
         this.transformDocument(this.options.query)
       : combinedOptions.query;
 
     let wasUpdated = false;
 
-    const updateQuery = fetchMoreOptions?.updateQuery;
     const isCached = this.options.fetchPolicy !== "no-cache";
 
     if (!isCached) {
@@ -792,7 +792,6 @@ Did you mean to call refetch(variables) instead of refetch({ variables })?`,
           // fetchMore cache results back to this ObservableQuery.
           this.queryManager.cache.batch({
             update: (cache) => {
-              const { updateQuery } = fetchMoreOptions;
               if (updateQuery) {
                 cache.updateQuery(
                   {
diff --git a/src/core/watchQueryOptions.ts b/src/core/watchQueryOptions.ts
index ba30738aa13..f46bb7be109 100644
--- a/src/core/watchQueryOptions.ts
+++ b/src/core/watchQueryOptions.ts
@@ -21,6 +21,7 @@ import type {
   OnQueryUpdated,
   OperationVariables,
 } from "./types.js";
+import { Watch } from "typescript";
 
 /**
  * fetchPolicy determines where the client may return a result from. The options are:
@@ -135,13 +136,22 @@ export interface NextFetchPolicyContext<
   initialFetchPolicy: WatchQueryFetchPolicy;
 }
 
-export interface FetchMoreQueryOptions<TVariables, TData = unknown> {
+export type FetchMoreQueryOptions<
+  TVariables extends OperationVariables = OperationVariables,
+  TData = unknown,
+> = {
   /** {@inheritDoc @apollo/client!QueryOptionsDocumentation#query:member} */
-  query?: DocumentNode | TypedDocumentNode<TData, TVariables>;
-  /** {@inheritDoc @apollo/client!QueryOptionsDocumentation#variables:member} */
-  variables?: Partial<NoInfer<TVariables>>;
+  query: DocumentNode | TypedDocumentNode<TData, TVariables>;
+
+  /** {@inheritDoc @apollo/client!QueryOptionsDocumentation#errorPolicy:member} */
+  errorPolicy?: ErrorPolicy;
+
+  /** {@inheritDoc @apollo/client!QueryOptionsDocumentation#context:member} */
   context?: DefaultContext;
-}
+
+  /** {@inheritDoc @apollo/client!QueryOptionsDocumentation#fetchPolicy:member} */
+  fetchPolicy?: FetchPolicy;
+} & VariablesOption<NoInfer<TVariables>>;
 
 export type UpdateQueryOptions<TData, TVariables> = {
   variables?: TVariables;

From b65982b34d0fd052026a3760b815d6bdeb10ed03 Mon Sep 17 00:00:00 2001
From: Lenz Weber-Tronic <lorenz.weber-tronic@apollographql.com>
Date: Wed, 18 Jun 2025 18:49:59 +0200
Subject: [PATCH 02/10] adjust options

---
 src/core/ObservableQuery.ts   | 24 ++++++++++++++++--------
 src/core/watchQueryOptions.ts |  3 ---
 2 files changed, 16 insertions(+), 11 deletions(-)

diff --git a/src/core/ObservableQuery.ts b/src/core/ObservableQuery.ts
index fedc16f6657..a3e2f1d15cf 100644
--- a/src/core/ObservableQuery.ts
+++ b/src/core/ObservableQuery.ts
@@ -713,7 +713,6 @@ Did you mean to call refetch(variables) instead of refetch({ variables })?`,
     variables,
     context,
     errorPolicy,
-    fetchPolicy,
     updateQuery,
   }: FetchMoreQueryOptions<TFetchVars, TFetchData> & {
     updateQuery?: (
@@ -725,13 +724,22 @@ Did you mean to call refetch(variables) instead of refetch({ variables })?`,
     ) => Unmasked<TData>;
   }): Promise<QueryResult<TFetchData>> {
     const combinedOptions = {
-      ...compact(this.options, {
-        query,
-        variables,
-        context,
-        errorPolicy,
-        fetchPolicy,
-      }),
+      ...compact(
+        this.options,
+        { errorPolicy: "none" },
+        {
+          query,
+          context,
+          errorPolicy,
+        }
+      ),
+      variables:
+        query ? variables : (
+          {
+            ...this.variables,
+            ...variables,
+          }
+        ),
       // The fetchMore request goes immediately to the network and does
       // not automatically write its result to the cache (hence no-cache
       // instead of network-only), because we allow the caller of
diff --git a/src/core/watchQueryOptions.ts b/src/core/watchQueryOptions.ts
index f46bb7be109..30641b70801 100644
--- a/src/core/watchQueryOptions.ts
+++ b/src/core/watchQueryOptions.ts
@@ -148,9 +148,6 @@ export type FetchMoreQueryOptions<
 
   /** {@inheritDoc @apollo/client!QueryOptionsDocumentation#context:member} */
   context?: DefaultContext;
-
-  /** {@inheritDoc @apollo/client!QueryOptionsDocumentation#fetchPolicy:member} */
-  fetchPolicy?: FetchPolicy;
 } & VariablesOption<NoInfer<TVariables>>;
 
 export type UpdateQueryOptions<TData, TVariables> = {

From 71d8aebd7bc960bc6a3f425783b989fd0cda080f Mon Sep 17 00:00:00 2001
From: Lenz Weber-Tronic <lorenz.weber-tronic@apollographql.com>
Date: Wed, 18 Jun 2025 18:57:20 +0200
Subject: [PATCH 03/10] undo some type changes

---
 src/core/ObservableQuery.ts   | 4 ++--
 src/core/watchQueryOptions.ts | 1 -
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/core/ObservableQuery.ts b/src/core/ObservableQuery.ts
index a3e2f1d15cf..7cabed6cd9d 100644
--- a/src/core/ObservableQuery.ts
+++ b/src/core/ObservableQuery.ts
@@ -718,8 +718,8 @@ Did you mean to call refetch(variables) instead of refetch({ variables })?`,
     updateQuery?: (
       previousQueryResult: Unmasked<TData>,
       options: {
-        fetchMoreResult: Unmasked<TData>;
-        variables: NoInfer<TVariables>;
+        fetchMoreResult: Unmasked<TFetchData>;
+        variables: TFetchVars;
       }
     ) => Unmasked<TData>;
   }): Promise<QueryResult<TFetchData>> {
diff --git a/src/core/watchQueryOptions.ts b/src/core/watchQueryOptions.ts
index 30641b70801..3b6e8e2b876 100644
--- a/src/core/watchQueryOptions.ts
+++ b/src/core/watchQueryOptions.ts
@@ -21,7 +21,6 @@ import type {
   OnQueryUpdated,
   OperationVariables,
 } from "./types.js";
-import { Watch } from "typescript";
 
 /**
  * fetchPolicy determines where the client may return a result from. The options are:

From eae522e4211765d5957b1d70045bfaf99dc38385 Mon Sep 17 00:00:00 2001
From: Lenz Weber-Tronic <lorenz.weber-tronic@apollographql.com>
Date: Wed, 18 Jun 2025 19:16:56 +0200
Subject: [PATCH 04/10] fix up types

---
 src/core/ObservableQuery.ts                | 30 ++++++++++------------
 src/core/watchQueryOptions.ts              | 10 ++++----
 src/react/hooks/useLoadableQuery.ts        |  5 +---
 src/react/internal/cache/QueryReference.ts |  7 ++---
 src/react/internal/types.ts                | 13 ++--------
 5 files changed, 23 insertions(+), 42 deletions(-)

diff --git a/src/core/ObservableQuery.ts b/src/core/ObservableQuery.ts
index 7cabed6cd9d..0c01eca8152 100644
--- a/src/core/ObservableQuery.ts
+++ b/src/core/ObservableQuery.ts
@@ -49,18 +49,20 @@ import type {
 
 const { assign, hasOwnProperty } = Object;
 
-export interface FetchMoreOptions<
+export type FetchMoreOptions<
   TData = unknown,
-  TVariables = OperationVariables,
-> {
+  TVariables extends OperationVariables = OperationVariables,
+  TFetchData = TData,
+  TFetchVars extends OperationVariables = TVariables,
+> = FetchMoreQueryOptions<TFetchVars, TFetchData> & {
   updateQuery?: (
-    previousQueryResult: TData,
+    previousQueryResult: Unmasked<TData>,
     options: {
-      fetchMoreResult?: TData;
-      variables?: TVariables;
+      fetchMoreResult: Unmasked<TFetchData>;
+      variables: TFetchVars;
     }
-  ) => TData;
-}
+  ) => Unmasked<TData>;
+};
 
 interface TrackedOperation {
   /**
@@ -714,15 +716,9 @@ Did you mean to call refetch(variables) instead of refetch({ variables })?`,
     context,
     errorPolicy,
     updateQuery,
-  }: FetchMoreQueryOptions<TFetchVars, TFetchData> & {
-    updateQuery?: (
-      previousQueryResult: Unmasked<TData>,
-      options: {
-        fetchMoreResult: Unmasked<TFetchData>;
-        variables: TFetchVars;
-      }
-    ) => Unmasked<TData>;
-  }): Promise<QueryResult<TFetchData>> {
+  }: FetchMoreOptions<TData, TVariables, TFetchData, TFetchVars>): Promise<
+    QueryResult<TFetchData>
+  > {
     const combinedOptions = {
       ...compact(
         this.options,
diff --git a/src/core/watchQueryOptions.ts b/src/core/watchQueryOptions.ts
index 3b6e8e2b876..5633cf4740e 100644
--- a/src/core/watchQueryOptions.ts
+++ b/src/core/watchQueryOptions.ts
@@ -14,10 +14,10 @@ import type { IgnoreModifier } from "../cache/core/types/common.js";
 import type { ObservableQuery } from "./ObservableQuery.js";
 import type {
   DefaultContext,
-  NormalizedExecutionResult,
   InternalRefetchQueriesInclude,
   MutationQueryReducersMap,
   MutationUpdaterFunction,
+  NormalizedExecutionResult,
   OnQueryUpdated,
   OperationVariables,
 } from "./types.js";
@@ -140,14 +140,14 @@ export type FetchMoreQueryOptions<
   TData = unknown,
 > = {
   /** {@inheritDoc @apollo/client!QueryOptionsDocumentation#query:member} */
-  query: DocumentNode | TypedDocumentNode<TData, TVariables>;
-
+  query?: DocumentNode | TypedDocumentNode<TData, TVariables>;
+  /** {@inheritDoc @apollo/client!QueryOptionsDocumentation#variables:member} */
+  variables?: Partial<NoInfer<TVariables>>;
   /** {@inheritDoc @apollo/client!QueryOptionsDocumentation#errorPolicy:member} */
   errorPolicy?: ErrorPolicy;
-
   /** {@inheritDoc @apollo/client!QueryOptionsDocumentation#context:member} */
   context?: DefaultContext;
-} & VariablesOption<NoInfer<TVariables>>;
+};
 
 export type UpdateQueryOptions<TData, TVariables> = {
   variables?: TVariables;
diff --git a/src/react/hooks/useLoadableQuery.ts b/src/react/hooks/useLoadableQuery.ts
index dd8e17c2283..5f1e6affbcb 100644
--- a/src/react/hooks/useLoadableQuery.ts
+++ b/src/react/hooks/useLoadableQuery.ts
@@ -6,7 +6,6 @@ import type {
   DefaultContext,
   DocumentNode,
   ErrorPolicy,
-  FetchMoreQueryOptions,
   OperationVariables,
   RefetchWritePolicy,
   TypedDocumentNode,
@@ -234,9 +233,7 @@ export function useLoadableQuery<
         );
       }
 
-      const promise = internalQueryRef.fetchMore(
-        options as FetchMoreQueryOptions<TVariables, TData>
-      );
+      const promise = internalQueryRef.fetchMore(options);
 
       setQueryRef(wrapQueryRef(internalQueryRef));
 
diff --git a/src/react/internal/cache/QueryReference.ts b/src/react/internal/cache/QueryReference.ts
index 0489e6a5af3..df456d6601c 100644
--- a/src/react/internal/cache/QueryReference.ts
+++ b/src/react/internal/cache/QueryReference.ts
@@ -5,6 +5,7 @@ import { filter } from "rxjs";
 import type {
   ApolloQueryResult,
   DataState,
+  FetchMoreOptions,
   ObservableQuery,
   OperationVariables,
   QueryResult,
@@ -30,10 +31,6 @@ type Listener<TData, TStates extends DataState<TData>["dataState"]> = (
   promise: QueryRefPromise<TData, TStates>
 ) => void;
 
-type FetchMoreOptions<TData> = Parameters<
-  ObservableQuery<TData>["fetchMore"]
->[0];
-
 const QUERY_REFERENCE_SYMBOL: unique symbol = Symbol.for(
   "apollo.internal.queryRef"
 );
@@ -350,7 +347,7 @@ export class InternalQueryReference<
     return this.initiateFetch(this.observable.refetch(variables));
   }
 
-  fetchMore(options: FetchMoreOptions<TData>) {
+  fetchMore(options: FetchMoreOptions<TData, any>) {
     return this.initiateFetch(this.observable.fetchMore<TData>(options));
   }
 
diff --git a/src/react/internal/types.ts b/src/react/internal/types.ts
index f7cf0485c85..05fb489c77f 100644
--- a/src/react/internal/types.ts
+++ b/src/react/internal/types.ts
@@ -1,9 +1,8 @@
 import type {
-  FetchMoreQueryOptions,
+  FetchMoreOptions,
   MaybeMasked,
   OperationVariables,
   QueryResult,
-  Unmasked,
 } from "@apollo/client";
 
 export type RefetchFunction<TData, TVariables extends OperationVariables> = (
@@ -11,13 +10,5 @@ export type RefetchFunction<TData, TVariables extends OperationVariables> = (
 ) => Promise<QueryResult<TData>>;
 
 export type FetchMoreFunction<TData, TVariables extends OperationVariables> = (
-  fetchMoreOptions: FetchMoreQueryOptions<TVariables, TData> & {
-    updateQuery?: (
-      previousQueryResult: Unmasked<TData>,
-      options: {
-        fetchMoreResult: Unmasked<TData>;
-        variables: TVariables;
-      }
-    ) => Unmasked<TData>;
-  }
+  fetchMoreOptions: FetchMoreOptions<TData, TVariables>
 ) => Promise<QueryResult<MaybeMasked<TData>>>;

From db847ec19cf243f51d721732c1e646bdd088b1e4 Mon Sep 17 00:00:00 2001
From: Lenz Weber-Tronic <lorenz.weber-tronic@apollographql.com>
Date: Wed, 18 Jun 2025 19:44:06 +0200
Subject: [PATCH 05/10] changesets

---
 .changeset/mighty-carrots-bathe.md |  7 +++++++
 .changeset/old-melons-double.md    | 11 +++++++++++
 2 files changed, 18 insertions(+)
 create mode 100644 .changeset/mighty-carrots-bathe.md
 create mode 100644 .changeset/old-melons-double.md

diff --git a/.changeset/mighty-carrots-bathe.md b/.changeset/mighty-carrots-bathe.md
new file mode 100644
index 00000000000..8fb9e1e13b6
--- /dev/null
+++ b/.changeset/mighty-carrots-bathe.md
@@ -0,0 +1,7 @@
+---
+"@apollo/client": minor
+---
+
+Allow passing `errorPolicy` option to `fetchMore` and change default value.
+
+Also, the `FetchMoreOptions` type now also includes the `FetchMoreQueryOptions` type.
diff --git a/.changeset/old-melons-double.md b/.changeset/old-melons-double.md
new file mode 100644
index 00000000000..8fbe2b62987
--- /dev/null
+++ b/.changeset/old-melons-double.md
@@ -0,0 +1,11 @@
+---
+"@apollo/client": major
+---
+
+Rework option handling for `fetchMore`.
+
+* Previously, if the `query` option was specified, no options would be inherited
+from the underlying `ObservableQuery`.
+Now, even if `query` is specified, all unspecified options except for `variables` will be inherited from the underlying `ObservableQuery`.
+* If `query` is not specified, `variables` will still be shallowly merged with the `variables` of the underlying `ObservableQuery` (this also was the previous behaviour).
+* `errorPolicy` of `fetchMore` will now always default to `"none"` instead of being inherited.

From 33b41ed905d3a4b062c1db877d446a3301ba59c3 Mon Sep 17 00:00:00 2001
From: Lenz Weber-Tronic <lorenz.weber-tronic@apollographql.com>
Date: Wed, 18 Jun 2025 21:09:15 +0200
Subject: [PATCH 06/10] type changes

---
 .changeset/mighty-carrots-bathe.md     |  3 +--
 .changeset/sixty-bears-bathe.md        |  6 +++++
 src/core/ObservableQuery.ts            | 31 ++++++++++++++++----------
 src/core/index.ts                      |  3 +--
 src/core/watchQueryOptions.ts          | 14 ------------
 src/react/hooks/useBackgroundQuery.ts  |  3 +--
 src/react/hooks/useLazyQuery.ts        | 18 ++++++---------
 src/react/hooks/useQuery.ts            | 19 +++++++---------
 src/react/hooks/useQueryRefHandlers.ts |  9 +++++---
 src/react/internal/types.ts            |  7 ++++--
 10 files changed, 54 insertions(+), 59 deletions(-)
 create mode 100644 .changeset/sixty-bears-bathe.md

diff --git a/.changeset/mighty-carrots-bathe.md b/.changeset/mighty-carrots-bathe.md
index 8fb9e1e13b6..1a011f94bc4 100644
--- a/.changeset/mighty-carrots-bathe.md
+++ b/.changeset/mighty-carrots-bathe.md
@@ -2,6 +2,5 @@
 "@apollo/client": minor
 ---
 
-Allow passing `errorPolicy` option to `fetchMore` and change default value.
+Allow passing `errorPolicy` option to `fetchMore` and change default value to "none".
 
-Also, the `FetchMoreOptions` type now also includes the `FetchMoreQueryOptions` type.
diff --git a/.changeset/sixty-bears-bathe.md b/.changeset/sixty-bears-bathe.md
new file mode 100644
index 00000000000..183099382a3
--- /dev/null
+++ b/.changeset/sixty-bears-bathe.md
@@ -0,0 +1,6 @@
+---
+"@apollo/client": minor
+---
+
+The `FetchMoreQueryOptions` type has been inlined into `FetchMoreOptions`, and
+`FetchMoreQueryOptions` has been removed.
diff --git a/src/core/ObservableQuery.ts b/src/core/ObservableQuery.ts
index 0c01eca8152..279985fa2e0 100644
--- a/src/core/ObservableQuery.ts
+++ b/src/core/ObservableQuery.ts
@@ -37,8 +37,8 @@ import type {
 } from "./types.js";
 import type {
   ErrorPolicy,
-  FetchMoreQueryOptions,
   NextFetchPolicyContext,
+  QueryOptions,
   RefetchWritePolicy,
   SubscribeToMoreOptions,
   UpdateQueryMapFn,
@@ -50,11 +50,19 @@ import type {
 const { assign, hasOwnProperty } = Object;
 
 export type FetchMoreOptions<
-  TData = unknown,
-  TVariables extends OperationVariables = OperationVariables,
+  TData,
+  TVariables extends OperationVariables,
   TFetchData = TData,
   TFetchVars extends OperationVariables = TVariables,
-> = FetchMoreQueryOptions<TFetchVars, TFetchData> & {
+> = {
+  /** {@inheritDoc @apollo/client!QueryOptionsDocumentation#query:member} */
+  query?: DocumentNode | TypedDocumentNode<TFetchData, TFetchVars>;
+  /** {@inheritDoc @apollo/client!QueryOptionsDocumentation#variables:member} */
+  variables?: Partial<NoInfer<TFetchVars>>;
+  /** {@inheritDoc @apollo/client!QueryOptionsDocumentation#errorPolicy:member} */
+  errorPolicy?: ErrorPolicy;
+  /** {@inheritDoc @apollo/client!QueryOptionsDocumentation#context:member} */
+  context?: DefaultContext;
   updateQuery?: (
     previousQueryResult: Unmasked<TData>,
     options: {
@@ -729,13 +737,12 @@ Did you mean to call refetch(variables) instead of refetch({ variables })?`,
           errorPolicy,
         }
       ),
-      variables:
-        query ? variables : (
-          {
-            ...this.variables,
-            ...variables,
-          }
-        ),
+      variables: (query ? variables : (
+        {
+          ...this.variables,
+          ...variables,
+        }
+      )) as TFetchVars,
       // The fetchMore request goes immediately to the network and does
       // not automatically write its result to the cache (hence no-cache
       // instead of network-only), because we allow the caller of
@@ -743,7 +750,7 @@ Did you mean to call refetch(variables) instead of refetch({ variables })?`,
       // the data gets written to the cache.
       fetchPolicy: "no-cache",
       notifyOnNetworkStatusChange: this.options.notifyOnNetworkStatusChange,
-    } as WatchQueryOptions<TFetchVars, TFetchData>;
+    } as QueryOptions<TFetchVars, TFetchData>;
 
     combinedOptions.query = this.transformDocument(combinedOptions.query);
 
diff --git a/src/core/index.ts b/src/core/index.ts
index 11ac17daf18..7ac63579216 100644
--- a/src/core/index.ts
+++ b/src/core/index.ts
@@ -6,7 +6,6 @@ export type { FetchMoreOptions } from "./ObservableQuery.js";
 export { ObservableQuery } from "./ObservableQuery.js";
 export type {
   ErrorPolicy,
-  FetchMoreQueryOptions,
   FetchPolicy,
   MutationFetchPolicy,
   MutationOptions,
@@ -27,7 +26,6 @@ export type {
   DataState,
   DefaultContext,
   ErrorLike,
-  NormalizedExecutionResult,
   GetDataState,
   InternalRefetchQueriesInclude,
   InternalRefetchQueriesMap,
@@ -39,6 +37,7 @@ export type {
   MutationQueryReducer,
   MutationQueryReducersMap,
   MutationUpdaterFunction,
+  NormalizedExecutionResult,
   OnQueryUpdated,
   OperationVariables,
   QueryResult,
diff --git a/src/core/watchQueryOptions.ts b/src/core/watchQueryOptions.ts
index 5633cf4740e..a2a7898ec06 100644
--- a/src/core/watchQueryOptions.ts
+++ b/src/core/watchQueryOptions.ts
@@ -135,20 +135,6 @@ export interface NextFetchPolicyContext<
   initialFetchPolicy: WatchQueryFetchPolicy;
 }
 
-export type FetchMoreQueryOptions<
-  TVariables extends OperationVariables = OperationVariables,
-  TData = unknown,
-> = {
-  /** {@inheritDoc @apollo/client!QueryOptionsDocumentation#query:member} */
-  query?: DocumentNode | TypedDocumentNode<TData, TVariables>;
-  /** {@inheritDoc @apollo/client!QueryOptionsDocumentation#variables:member} */
-  variables?: Partial<NoInfer<TVariables>>;
-  /** {@inheritDoc @apollo/client!QueryOptionsDocumentation#errorPolicy:member} */
-  errorPolicy?: ErrorPolicy;
-  /** {@inheritDoc @apollo/client!QueryOptionsDocumentation#context:member} */
-  context?: DefaultContext;
-};
-
 export type UpdateQueryOptions<TData, TVariables> = {
   variables?: TVariables;
 } & (
diff --git a/src/react/hooks/useBackgroundQuery.ts b/src/react/hooks/useBackgroundQuery.ts
index 9f7f466205b..8e0f6ab44c5 100644
--- a/src/react/hooks/useBackgroundQuery.ts
+++ b/src/react/hooks/useBackgroundQuery.ts
@@ -6,7 +6,6 @@ import type {
   DefaultContext,
   DocumentNode,
   ErrorPolicy,
-  FetchMoreQueryOptions,
   OperationVariables,
   RefetchWritePolicy,
   TypedDocumentNode,
@@ -382,7 +381,7 @@ function useBackgroundQuery_<
 
   const fetchMore: FetchMoreFunction<TData, TVariables> = React.useCallback(
     (options) => {
-      const promise = queryRef.fetchMore(options as FetchMoreQueryOptions<any>);
+      const promise = queryRef.fetchMore(options);
 
       setWrappedQueryRef(wrapQueryRef(queryRef));
 
diff --git a/src/react/hooks/useLazyQuery.ts b/src/react/hooks/useLazyQuery.ts
index bb8dcb3b9b1..cf0e6a2b8ba 100644
--- a/src/react/hooks/useLazyQuery.ts
+++ b/src/react/hooks/useLazyQuery.ts
@@ -10,7 +10,7 @@ import type {
   DefaultContext,
   ErrorLike,
   ErrorPolicy,
-  FetchMoreQueryOptions,
+  FetchMoreOptions,
   GetDataState,
   MaybeMasked,
   ObservableQuery,
@@ -18,7 +18,6 @@ import type {
   QueryResult,
   RefetchWritePolicy,
   SubscribeToMoreFunction,
-  Unmasked,
   UpdateQueryMapFn,
   WatchQueryFetchPolicy,
   WatchQueryOptions,
@@ -106,15 +105,12 @@ export declare namespace useLazyQuery {
       TFetchData = TData,
       TFetchVars extends OperationVariables = TVariables,
     >(
-      fetchMoreOptions: FetchMoreQueryOptions<TFetchVars, TFetchData> & {
-        updateQuery?: (
-          previousQueryResult: Unmasked<TData>,
-          options: {
-            fetchMoreResult: Unmasked<TFetchData>;
-            variables: TFetchVars;
-          }
-        ) => Unmasked<TData>;
-      }
+      fetchMoreOptions: FetchMoreOptions<
+        TData,
+        TVariables,
+        TFetchData,
+        TFetchVars
+      >
     ) => Promise<QueryResult<MaybeMasked<TFetchData>>>;
 
     /** {@inheritDoc @apollo/client!QueryResultDocumentation#client:member} */
diff --git a/src/react/hooks/useQuery.ts b/src/react/hooks/useQuery.ts
index 4cc003c6752..a43fc7977c3 100644
--- a/src/react/hooks/useQuery.ts
+++ b/src/react/hooks/useQuery.ts
@@ -23,7 +23,7 @@ import type {
   DocumentNode,
   ErrorLike,
   ErrorPolicy,
-  FetchMoreQueryOptions,
+  FetchMoreOptions,
   GetDataState,
   ObservableQuery,
   OperationVariables,
@@ -36,7 +36,7 @@ import type {
   WatchQueryOptions,
 } from "@apollo/client";
 import { NetworkStatus } from "@apollo/client";
-import type { MaybeMasked, Unmasked } from "@apollo/client/masking";
+import type { MaybeMasked } from "@apollo/client/masking";
 import type {
   NoInfer,
   VariablesOption,
@@ -152,15 +152,12 @@ export declare namespace useQuery {
       TFetchData = TData,
       TFetchVars extends OperationVariables = TVariables,
     >(
-      fetchMoreOptions: FetchMoreQueryOptions<TFetchVars, TFetchData> & {
-        updateQuery?: (
-          previousQueryResult: Unmasked<TData>,
-          options: {
-            fetchMoreResult: Unmasked<TFetchData>;
-            variables: TFetchVars;
-          }
-        ) => Unmasked<TData>;
-      }
+      fetchMoreOptions: FetchMoreOptions<
+        TData,
+        TVariables,
+        TFetchData,
+        TFetchVars
+      >
     ) => Promise<QueryResult<MaybeMasked<TFetchData>>>;
   } & GetDataState<MaybeMasked<TData>, TStates>;
 }
diff --git a/src/react/hooks/useQueryRefHandlers.ts b/src/react/hooks/useQueryRefHandlers.ts
index 327ad3d2d6f..39a701c6bae 100644
--- a/src/react/hooks/useQueryRefHandlers.ts
+++ b/src/react/hooks/useQueryRefHandlers.ts
@@ -1,8 +1,11 @@
 import * as React from "react";
 
-import type { DataState, OperationVariables } from "@apollo/client";
+import type {
+  DataState,
+  FetchMoreOptions,
+  OperationVariables,
+} from "@apollo/client";
 import type { SubscribeToMoreFunction } from "@apollo/client";
-import type { FetchMoreQueryOptions } from "@apollo/client";
 import type { ApolloClient } from "@apollo/client";
 import type { ObservableQuery } from "@apollo/client";
 import type {
@@ -113,7 +116,7 @@ function useQueryRefHandlers_<
   const fetchMore: FetchMoreFunction<TData, TVariables> = React.useCallback(
     (options) => {
       const promise = internalQueryRef.fetchMore(
-        options as FetchMoreQueryOptions<any, any>
+        options as FetchMoreOptions<any, any>
       );
 
       setWrappedQueryRef(wrapQueryRef(internalQueryRef));
diff --git a/src/react/internal/types.ts b/src/react/internal/types.ts
index 05fb489c77f..603e3dfd91c 100644
--- a/src/react/internal/types.ts
+++ b/src/react/internal/types.ts
@@ -9,6 +9,9 @@ export type RefetchFunction<TData, TVariables extends OperationVariables> = (
   variables?: Partial<TVariables>
 ) => Promise<QueryResult<TData>>;
 
-export type FetchMoreFunction<TData, TVariables extends OperationVariables> = (
-  fetchMoreOptions: FetchMoreOptions<TData, TVariables>
+export type FetchMoreFunction<TData, TVariables extends OperationVariables> = <
+  TFetchData = TData,
+  TFetchVars extends OperationVariables = TVariables,
+>(
+  fetchMoreOptions: FetchMoreOptions<TData, TVariables, TFetchData, TFetchVars>
 ) => Promise<QueryResult<MaybeMasked<TData>>>;

From 7c6f7ee96c517ced66888a7c4fbb6a14455c9750 Mon Sep 17 00:00:00 2001
From: Lenz Weber-Tronic <lorenz.weber-tronic@apollographql.com>
Date: Wed, 18 Jun 2025 21:15:04 +0200
Subject: [PATCH 07/10] changeset changes

---
 .changeset/old-melons-double.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/.changeset/old-melons-double.md b/.changeset/old-melons-double.md
index 8fbe2b62987..bde0eda5a7e 100644
--- a/.changeset/old-melons-double.md
+++ b/.changeset/old-melons-double.md
@@ -7,5 +7,5 @@ Rework option handling for `fetchMore`.
 * Previously, if the `query` option was specified, no options would be inherited
 from the underlying `ObservableQuery`.
 Now, even if `query` is specified, all unspecified options except for `variables` will be inherited from the underlying `ObservableQuery`.
-* If `query` is not specified, `variables` will still be shallowly merged with the `variables` of the underlying `ObservableQuery` (this also was the previous behaviour).
-* `errorPolicy` of `fetchMore` will now always default to `"none"` instead of being inherited.
+* If `query` is not specified, `variables` will still be shallowly merged with the `variables` of the underlying `ObservableQuery`. If a `query` option is specified, the `variables` passed to `fetchMore` are used instead.
+* `errorPolicy` of `fetchMore` will now always default to `"none"` instead of inherited from the `ObservableQuery` options. This can prevent accidental cache writes of partial data for a paginated query. To opt into receive partial data that may be written to the cache, pass an `errorPolicy` to `fetchMore` to override the default.

From 5abbe5b52d60418556a3f8826e8fd4861124d38b Mon Sep 17 00:00:00 2001
From: Lenz Weber-Tronic <lorenz.weber-tronic@apollographql.com>
Date: Wed, 18 Jun 2025 21:17:26 +0200
Subject: [PATCH 08/10] fixup & chores

---
 .api-reports/api-report-core.api.md           | 36 ++++-------
 .api-reports/api-report-react.api.md          | 63 ++++++++-----------
 .api-reports/api-report-react_internal.api.md | 17 +----
 .api-reports/api-report.api.md                | 38 +++++------
 .size-limits.json                             |  8 +--
 src/react/internal/cache/QueryReference.ts    |  2 +-
 6 files changed, 61 insertions(+), 103 deletions(-)

diff --git a/.api-reports/api-report-core.api.md b/.api-reports/api-report-core.api.md
index bd7c543b21f..bb88e62c225 100644
--- a/.api-reports/api-report-core.api.md
+++ b/.api-reports/api-report-core.api.md
@@ -305,21 +305,16 @@ export { execute }
 export { fallbackHttpConfig }
 
 // @public (undocumented)
-export interface FetchMoreOptions<TData = unknown, TVariables = OperationVariables> {
-    // (undocumented)
-    updateQuery?: (previousQueryResult: TData, options: {
-        fetchMoreResult?: TData;
-        variables?: TVariables;
-    }) => TData;
-}
-
-// @public (undocumented)
-export interface FetchMoreQueryOptions<TVariables, TData = unknown> {
-    // (undocumented)
+export type FetchMoreOptions<TData, TVariables extends OperationVariables, TFetchData = TData, TFetchVars extends OperationVariables = TVariables> = {
+    query?: DocumentNode_2 | TypedDocumentNode<TFetchData, TFetchVars>;
+    variables?: Partial<NoInfer<TFetchVars>>;
+    errorPolicy?: ErrorPolicy;
     context?: DefaultContext;
-    query?: DocumentNode_2 | TypedDocumentNode<TData, TVariables>;
-    variables?: Partial<NoInfer_2<TVariables>>;
-}
+    updateQuery?: (previousQueryResult: Unmasked<TData>, options: {
+        fetchMoreResult: Unmasked<TFetchData>;
+        variables: TFetchVars;
+    }) => Unmasked<TData>;
+};
 
 // @public
 export type FetchPolicy = "cache-first" | "network-only" | "cache-only" | "no-cache";
@@ -586,12 +581,7 @@ export class ObservableQuery<TData = unknown, TVariables extends OperationVariab
         transformedQuery?: DocumentNode_2 | TypedDocumentNode<TData, TVariables>;
         queryId?: string;
     });
-    fetchMore<TFetchData = TData, TFetchVars extends OperationVariables = TVariables>(fetchMoreOptions: FetchMoreQueryOptions<TFetchVars, TFetchData> & {
-        updateQuery?: (previousQueryResult: Unmasked<TData>, options: {
-            fetchMoreResult: Unmasked<TFetchData>;
-            variables: TFetchVars;
-        }) => Unmasked<TData>;
-    }): Promise<QueryResult<TFetchData>>;
+    fetchMore<TFetchData = TData, TFetchVars extends OperationVariables = TVariables>({ query, variables, context, errorPolicy, updateQuery, }: FetchMoreOptions<TData, TVariables, TFetchData, TFetchVars>): Promise<QueryResult<TFetchData>>;
     // @internal @deprecated (undocumented)
     getCacheDiff({ optimistic }?: {
         optimistic?: boolean | undefined;
@@ -1041,10 +1031,10 @@ export type WatchQueryOptions<TVariables extends OperationVariables = OperationV
 
 // Warnings were encountered during analysis:
 //
-// src/core/ObservableQuery.ts:133:5 - (ae-forgotten-export) The symbol "NextFetchPolicyContext" needs to be exported by the entry point index.d.ts
-// src/core/ObservableQuery.ts:293:5 - (ae-forgotten-export) The symbol "QueryManager" needs to be exported by the entry point index.d.ts
+// src/core/ObservableQuery.ts:143:5 - (ae-forgotten-export) The symbol "NextFetchPolicyContext" needs to be exported by the entry point index.d.ts
+// src/core/ObservableQuery.ts:303:5 - (ae-forgotten-export) The symbol "QueryManager" needs to be exported by the entry point index.d.ts
 // src/core/QueryManager.ts:187:5 - (ae-forgotten-export) The symbol "MutationStoreValue" needs to be exported by the entry point index.d.ts
-// src/core/watchQueryOptions.ts:261:3 - (ae-forgotten-export) The symbol "IgnoreModifier" needs to be exported by the entry point index.d.ts
+// src/core/watchQueryOptions.ts:253:3 - (ae-forgotten-export) The symbol "IgnoreModifier" needs to be exported by the entry point index.d.ts
 
 // (No @packageDocumentation comment for this package)
 
diff --git a/.api-reports/api-report-react.api.md b/.api-reports/api-report-react.api.md
index cb390f69d82..ad7beba2682 100644
--- a/.api-reports/api-report-react.api.md
+++ b/.api-reports/api-report-react.api.md
@@ -22,7 +22,7 @@ import { DocumentTransform } from '@apollo/client/utilities';
 import type { ErrorLike as ErrorLike_2 } from '@apollo/client';
 import type { ErrorPolicy as ErrorPolicy_2 } from '@apollo/client';
 import type { FetchMoreFunction } from '@apollo/client/react/internal';
-import type { FetchMoreQueryOptions as FetchMoreQueryOptions_2 } from '@apollo/client';
+import type { FetchMoreOptions as FetchMoreOptions_2 } from '@apollo/client';
 import type { FetchPolicy as FetchPolicy_2 } from '@apollo/client';
 import type { FetchResult } from '@apollo/client/link';
 import type { FormattedExecutionResult } from 'graphql';
@@ -290,12 +290,16 @@ interface ErrorLike {
 type ErrorPolicy = "none" | "ignore" | "all";
 
 // @public (undocumented)
-interface FetchMoreQueryOptions<TVariables, TData = unknown> {
-    // (undocumented)
+type FetchMoreOptions<TData, TVariables extends OperationVariables_2, TFetchData = TData, TFetchVars extends OperationVariables_2 = TVariables> = {
+    query?: DocumentNode | TypedDocumentNode<TFetchData, TFetchVars>;
+    variables?: Partial<NoInfer<TFetchVars>>;
+    errorPolicy?: ErrorPolicy;
     context?: DefaultContext;
-    query?: DocumentNode | TypedDocumentNode<TData, TVariables>;
-    variables?: Partial<NoInfer_2<TVariables>>;
-}
+    updateQuery?: (previousQueryResult: Unmasked<TData>, options: {
+        fetchMoreResult: Unmasked<TFetchData>;
+        variables: TFetchVars;
+    }) => Unmasked<TData>;
+};
 
 // @public
 type FetchPolicy = "cache-first" | "network-only" | "cache-only" | "no-cache";
@@ -560,13 +564,8 @@ class ObservableQuery<TData = unknown, TVariables extends OperationVariables_2 =
         transformedQuery?: DocumentNode | TypedDocumentNode<TData, TVariables>;
         queryId?: string;
     });
-    // Warning: (ae-forgotten-export) The symbol "FetchMoreQueryOptions" needs to be exported by the entry point index.d.ts
-    fetchMore<TFetchData = TData, TFetchVars extends OperationVariables_2 = TVariables>(fetchMoreOptions: FetchMoreQueryOptions<TFetchVars, TFetchData> & {
-        updateQuery?: (previousQueryResult: Unmasked<TData>, options: {
-            fetchMoreResult: Unmasked<TFetchData>;
-            variables: TFetchVars;
-        }) => Unmasked<TData>;
-    }): Promise<QueryResult_2<TFetchData>>;
+    // Warning: (ae-forgotten-export) The symbol "FetchMoreOptions" needs to be exported by the entry point index.d.ts
+    fetchMore<TFetchData = TData, TFetchVars extends OperationVariables_2 = TVariables>({ query, variables, context, errorPolicy, updateQuery, }: FetchMoreOptions<TData, TVariables, TFetchData, TFetchVars>): Promise<QueryResult_2<TFetchData>>;
     // @internal @deprecated (undocumented)
     getCacheDiff({ optimistic }?: {
         optimistic?: boolean | undefined;
@@ -1225,12 +1224,7 @@ export namespace useLazyQuery {
         subscribeToMore: SubscribeToMoreFunction<TData, TVariables>;
         updateQuery: (mapFn: UpdateQueryMapFn_2<TData, TVariables>) => void;
         refetch: (variables?: Partial<TVariables>) => Promise<QueryResult_3<MaybeMasked_2<TData>>>;
-        fetchMore: <TFetchData = TData, TFetchVars extends OperationVariables = TVariables>(fetchMoreOptions: FetchMoreQueryOptions_2<TFetchVars, TFetchData> & {
-            updateQuery?: (previousQueryResult: Unmasked_2<TData>, options: {
-                fetchMoreResult: Unmasked_2<TFetchData>;
-                variables: TFetchVars;
-            }) => Unmasked_2<TData>;
-        }) => Promise<QueryResult_3<MaybeMasked_2<TFetchData>>>;
+        fetchMore: <TFetchData = TData, TFetchVars extends OperationVariables = TVariables>(fetchMoreOptions: FetchMoreOptions_2<TData, TVariables, TFetchData, TFetchVars>) => Promise<QueryResult_3<MaybeMasked_2<TFetchData>>>;
         client: ApolloClient;
         observable: ObservableQuery_2<TData, TVariables>;
         previousData?: MaybeMasked_2<TData>;
@@ -1410,12 +1404,7 @@ export namespace useQuery {
         updateQuery: (mapFn: UpdateQueryMapFn_2<TData, TVariables>) => void;
         refetch: (variables?: Partial<TVariables>) => Promise<QueryResult_3<MaybeMasked<TData>>>;
         variables: TVariables;
-        fetchMore: <TFetchData = TData, TFetchVars extends OperationVariables = TVariables>(fetchMoreOptions: FetchMoreQueryOptions_2<TFetchVars, TFetchData> & {
-            updateQuery?: (previousQueryResult: Unmasked<TData>, options: {
-                fetchMoreResult: Unmasked<TFetchData>;
-                variables: TFetchVars;
-            }) => Unmasked<TData>;
-        }) => Promise<QueryResult_3<MaybeMasked<TFetchData>>>;
+        fetchMore: <TFetchData = TData, TFetchVars extends OperationVariables = TVariables>(fetchMoreOptions: FetchMoreOptions_2<TData, TVariables, TFetchData, TFetchVars>) => Promise<QueryResult_3<MaybeMasked<TFetchData>>>;
     } & GetDataState_2<MaybeMasked<TData>, TStates>;
 }
 
@@ -1640,23 +1629,23 @@ type WatchQueryOptions_2<TVariables extends OperationVariables_2 = OperationVari
 
 // Warnings were encountered during analysis:
 //
-// src/core/ObservableQuery.ts:133:5 - (ae-forgotten-export) The symbol "NextFetchPolicyContext" needs to be exported by the entry point index.d.ts
-// src/core/ObservableQuery.ts:145:5 - (ae-forgotten-export) The symbol "RefetchWritePolicy" needs to be exported by the entry point index.d.ts
-// src/core/ObservableQuery.ts:293:5 - (ae-forgotten-export) The symbol "QueryManager" needs to be exported by the entry point index.d.ts
+// src/core/ObservableQuery.ts:63:3 - (ae-forgotten-export) The symbol "ErrorPolicy" needs to be exported by the entry point index.d.ts
+// src/core/ObservableQuery.ts:143:5 - (ae-forgotten-export) The symbol "NextFetchPolicyContext" needs to be exported by the entry point index.d.ts
+// src/core/ObservableQuery.ts:155:5 - (ae-forgotten-export) The symbol "RefetchWritePolicy" needs to be exported by the entry point index.d.ts
+// src/core/ObservableQuery.ts:303:5 - (ae-forgotten-export) The symbol "QueryManager" needs to be exported by the entry point index.d.ts
 // src/core/QueryManager.ts:187:5 - (ae-forgotten-export) The symbol "MutationStoreValue" needs to be exported by the entry point index.d.ts
 // src/core/types.ts:236:3 - (ae-forgotten-export) The symbol "ErrorLike" needs to be exported by the entry point index.d.ts
 // src/core/types.ts:238:3 - (ae-forgotten-export) The symbol "NetworkStatus" needs to be exported by the entry point index.d.ts
 // src/core/types.ts:255:7 - (ae-forgotten-export) The symbol "Streaming" needs to be exported by the entry point index.d.ts
 // src/core/types.ts:308:3 - (ae-forgotten-export) The symbol "MutationQueryReducer" needs to be exported by the entry point index.d.ts
-// src/core/watchQueryOptions.ts:186:3 - (ae-forgotten-export) The symbol "UpdateQueryOptions" needs to be exported by the entry point index.d.ts
-// src/core/watchQueryOptions.ts:261:3 - (ae-forgotten-export) The symbol "IgnoreModifier" needs to be exported by the entry point index.d.ts
-// src/core/watchQueryOptions.ts:269:3 - (ae-forgotten-export) The symbol "MutationQueryReducersMap" needs to be exported by the entry point index.d.ts
-// src/core/watchQueryOptions.ts:272:3 - (ae-forgotten-export) The symbol "NormalizedExecutionResult" needs to be exported by the entry point index.d.ts
-// src/core/watchQueryOptions.ts:282:3 - (ae-forgotten-export) The symbol "MutationUpdaterFunction" needs to be exported by the entry point index.d.ts
-// src/core/watchQueryOptions.ts:285:3 - (ae-forgotten-export) The symbol "OnQueryUpdated" needs to be exported by the entry point index.d.ts
-// src/core/watchQueryOptions.ts:288:3 - (ae-forgotten-export) The symbol "ErrorPolicy" needs to be exported by the entry point index.d.ts
-// src/core/watchQueryOptions.ts:294:3 - (ae-forgotten-export) The symbol "MutationFetchPolicy" needs to be exported by the entry point index.d.ts
-// src/react/hooks/useLoadableQuery.ts:71:7 - (ae-forgotten-export) The symbol "ResetFunction" needs to be exported by the entry point index.d.ts
+// src/core/watchQueryOptions.ts:178:3 - (ae-forgotten-export) The symbol "UpdateQueryOptions" needs to be exported by the entry point index.d.ts
+// src/core/watchQueryOptions.ts:253:3 - (ae-forgotten-export) The symbol "IgnoreModifier" needs to be exported by the entry point index.d.ts
+// src/core/watchQueryOptions.ts:261:3 - (ae-forgotten-export) The symbol "MutationQueryReducersMap" needs to be exported by the entry point index.d.ts
+// src/core/watchQueryOptions.ts:264:3 - (ae-forgotten-export) The symbol "NormalizedExecutionResult" needs to be exported by the entry point index.d.ts
+// src/core/watchQueryOptions.ts:274:3 - (ae-forgotten-export) The symbol "MutationUpdaterFunction" needs to be exported by the entry point index.d.ts
+// src/core/watchQueryOptions.ts:277:3 - (ae-forgotten-export) The symbol "OnQueryUpdated" needs to be exported by the entry point index.d.ts
+// src/core/watchQueryOptions.ts:286:3 - (ae-forgotten-export) The symbol "MutationFetchPolicy" needs to be exported by the entry point index.d.ts
+// src/react/hooks/useLoadableQuery.ts:70:7 - (ae-forgotten-export) The symbol "ResetFunction" needs to be exported by the entry point index.d.ts
 // src/react/hooks/useSuspenseFragment.ts:75:5 - (ae-forgotten-export) The symbol "From" needs to be exported by the entry point index.d.ts
 
 // (No @packageDocumentation comment for this package)
diff --git a/.api-reports/api-report-react_internal.api.md b/.api-reports/api-report-react_internal.api.md
index 8f4f0f8770c..7e2cb3936d6 100644
--- a/.api-reports/api-report-react_internal.api.md
+++ b/.api-reports/api-report-react_internal.api.md
@@ -10,14 +10,13 @@ import type { createQueryPreloader } from '@apollo/client/react';
 import type { DataState } from '@apollo/client';
 import type { DecoratedPromise } from '@apollo/client/utilities/internal';
 import type { DocumentNode } from 'graphql';
-import type { FetchMoreQueryOptions } from '@apollo/client';
+import type { FetchMoreOptions } from '@apollo/client';
 import type { MaybeMasked } from '@apollo/client/masking';
 import type { MaybeMasked as MaybeMasked_2 } from '@apollo/client';
 import type { Observable } from 'rxjs';
 import type { ObservableQuery } from '@apollo/client';
 import type { OperationVariables } from '@apollo/client';
 import type { QueryResult } from '@apollo/client';
-import type { Unmasked } from '@apollo/client';
 import type { useBackgroundQuery } from '@apollo/client/react';
 import type { useFragment } from '@apollo/client/react';
 import type { useQuery } from '@apollo/client/react';
@@ -46,15 +45,7 @@ stringifiedVariables: string,
 ];
 
 // @public (undocumented)
-export type FetchMoreFunction<TData, TVariables extends OperationVariables> = (fetchMoreOptions: FetchMoreQueryOptions<TVariables, TData> & {
-    updateQuery?: (previousQueryResult: Unmasked<TData>, options: {
-        fetchMoreResult: Unmasked<TData>;
-        variables: TVariables;
-    }) => Unmasked<TData>;
-}) => Promise<QueryResult<MaybeMasked_2<TData>>>;
-
-// @public (undocumented)
-type FetchMoreOptions<TData> = Parameters<ObservableQuery<TData>["fetchMore"]>[0];
+export type FetchMoreFunction<TData, TVariables extends OperationVariables> = <TFetchData = TData, TFetchVars extends OperationVariables = TVariables>(fetchMoreOptions: FetchMoreOptions<TData, TVariables, TFetchData, TFetchVars>) => Promise<QueryResult<MaybeMasked_2<TData>>>;
 
 // @public (undocumented)
 type FragmentCacheKey = [
@@ -138,10 +129,8 @@ export class InternalQueryReference<TData = unknown, TStates extends DataState<T
     didChangeOptions(watchQueryOptions: ObservedOptions): boolean;
     // (undocumented)
     get disposed(): boolean;
-    // Warning: (ae-forgotten-export) The symbol "FetchMoreOptions" needs to be exported by the entry point index.d.ts
-    //
     // (undocumented)
-    fetchMore(options: FetchMoreOptions<TData>): Promise<QueryResult<TData>>;
+    fetchMore(options: FetchMoreOptions<TData, any, any, any>): Promise<QueryResult<TData>>;
     // (undocumented)
     readonly key: QueryKey;
     // Warning: (ae-forgotten-export) The symbol "Listener" needs to be exported by the entry point index.d.ts
diff --git a/.api-reports/api-report.api.md b/.api-reports/api-report.api.md
index efaa0f39fbe..6b10dbd84b4 100644
--- a/.api-reports/api-report.api.md
+++ b/.api-reports/api-report.api.md
@@ -841,22 +841,16 @@ export const fallbackHttpConfig: {
 };
 
 // @public (undocumented)
-export interface FetchMoreOptions<TData = unknown, TVariables = OperationVariables> {
-    // (undocumented)
-    updateQuery?: (previousQueryResult: TData, options: {
-        fetchMoreResult?: TData;
-        variables?: TVariables;
-    }) => TData;
-}
-
-// @public (undocumented)
-export interface FetchMoreQueryOptions<TVariables, TData = unknown> {
-    // (undocumented)
+export type FetchMoreOptions<TData, TVariables extends OperationVariables, TFetchData = TData, TFetchVars extends OperationVariables = TVariables> = {
+    query?: DocumentNode | TypedDocumentNode<TFetchData, TFetchVars>;
+    variables?: Partial<NoInfer<TFetchVars>>;
+    errorPolicy?: ErrorPolicy;
     context?: DefaultContext;
-    query?: DocumentNode | TypedDocumentNode<TData, TVariables>;
-    // Warning: (ae-forgotten-export) The symbol "NoInfer_2" needs to be exported by the entry point index.d.ts
-    variables?: Partial<NoInfer_2<TVariables>>;
-}
+    updateQuery?: (previousQueryResult: Unmasked<TData>, options: {
+        fetchMoreResult: Unmasked<TFetchData>;
+        variables: TFetchVars;
+    }) => Unmasked<TData>;
+};
 
 // @public
 export type FetchPolicy = "cache-first" | "network-only" | "cache-only" | "no-cache";
@@ -1521,6 +1515,7 @@ namespace LocalState {
 //
 // @public (undocumented)
 class LocalState<TResolvers extends LocalState.Resolvers = LocalState.Resolvers<DefaultContext>, TContext = InferContextValueFromResolvers<TResolvers>> {
+    // Warning: (ae-forgotten-export) The symbol "NoInfer_2" needs to be exported by the entry point index.d.ts
     constructor(...[options]: {} extends TResolvers ? [
     options?: LocalState.Options<TResolvers, NoInfer_2<TContext>>
     ] : [
@@ -1905,12 +1900,7 @@ export class ObservableQuery<TData = unknown, TVariables extends OperationVariab
         transformedQuery?: DocumentNode | TypedDocumentNode<TData, TVariables>;
         queryId?: string;
     });
-    fetchMore<TFetchData = TData, TFetchVars extends OperationVariables = TVariables>(fetchMoreOptions: FetchMoreQueryOptions<TFetchVars, TFetchData> & {
-        updateQuery?: (previousQueryResult: Unmasked<TData>, options: {
-            fetchMoreResult: Unmasked<TFetchData>;
-            variables: TFetchVars;
-        }) => Unmasked<TData>;
-    }): Promise<QueryResult<TFetchData>>;
+    fetchMore<TFetchData = TData, TFetchVars extends OperationVariables = TVariables>({ query, variables, context, errorPolicy, updateQuery, }: FetchMoreOptions<TData, TVariables, TFetchData, TFetchVars>): Promise<QueryResult<TFetchData>>;
     // @internal @deprecated (undocumented)
     getCacheDiff({ optimistic }?: {
         optimistic?: boolean | undefined;
@@ -2700,10 +2690,10 @@ interface WriteContext extends ReadMergeModifyContext {
 // src/cache/inmemory/policies.ts:166:3 - (ae-forgotten-export) The symbol "KeySpecifier" needs to be exported by the entry point index.d.ts
 // src/cache/inmemory/policies.ts:166:3 - (ae-forgotten-export) The symbol "KeyArgsFunction" needs to be exported by the entry point index.d.ts
 // src/cache/inmemory/types.ts:133:3 - (ae-forgotten-export) The symbol "KeyFieldsFunction" needs to be exported by the entry point index.d.ts
-// src/core/ObservableQuery.ts:133:5 - (ae-forgotten-export) The symbol "NextFetchPolicyContext" needs to be exported by the entry point index.d.ts
-// src/core/ObservableQuery.ts:293:5 - (ae-forgotten-export) The symbol "QueryManager" needs to be exported by the entry point index.d.ts
+// src/core/ObservableQuery.ts:143:5 - (ae-forgotten-export) The symbol "NextFetchPolicyContext" needs to be exported by the entry point index.d.ts
+// src/core/ObservableQuery.ts:303:5 - (ae-forgotten-export) The symbol "QueryManager" needs to be exported by the entry point index.d.ts
 // src/core/QueryManager.ts:187:5 - (ae-forgotten-export) The symbol "MutationStoreValue" needs to be exported by the entry point index.d.ts
-// src/core/watchQueryOptions.ts:261:3 - (ae-forgotten-export) The symbol "IgnoreModifier" needs to be exported by the entry point index.d.ts
+// src/core/watchQueryOptions.ts:253:3 - (ae-forgotten-export) The symbol "IgnoreModifier" needs to be exported by the entry point index.d.ts
 // src/local-state/LocalState.ts:140:5 - (ae-forgotten-export) The symbol "LocalState" needs to be exported by the entry point index.d.ts
 // src/local-state/LocalState.ts:174:7 - (ae-forgotten-export) The symbol "LocalState" needs to be exported by the entry point index.d.ts
 // src/local-state/LocalState.ts:194:7 - (ae-forgotten-export) The symbol "LocalState" needs to be exported by the entry point index.d.ts
diff --git a/.size-limits.json b/.size-limits.json
index e8fa89f8541..7c5de935ae0 100644
--- a/.size-limits.json
+++ b/.size-limits.json
@@ -1,6 +1,6 @@
 {
-  "import { ApolloClient, InMemoryCache, HttpLink } from \"@apollo/client\" (CJS)": 43543,
-  "import { ApolloClient, InMemoryCache, HttpLink } from \"@apollo/client\" (production) (CJS)": 38572,
-  "import { ApolloClient, InMemoryCache, HttpLink } from \"@apollo/client\"": 33302,
-  "import { ApolloClient, InMemoryCache, HttpLink } from \"@apollo/client\" (production)": 27599
+  "import { ApolloClient, InMemoryCache, HttpLink } from \"@apollo/client\" (CJS)": 43591,
+  "import { ApolloClient, InMemoryCache, HttpLink } from \"@apollo/client\" (production) (CJS)": 38584,
+  "import { ApolloClient, InMemoryCache, HttpLink } from \"@apollo/client\"": 33313,
+  "import { ApolloClient, InMemoryCache, HttpLink } from \"@apollo/client\" (production)": 27573
 }
diff --git a/src/react/internal/cache/QueryReference.ts b/src/react/internal/cache/QueryReference.ts
index df456d6601c..d3477c33cd8 100644
--- a/src/react/internal/cache/QueryReference.ts
+++ b/src/react/internal/cache/QueryReference.ts
@@ -347,7 +347,7 @@ export class InternalQueryReference<
     return this.initiateFetch(this.observable.refetch(variables));
   }
 
-  fetchMore(options: FetchMoreOptions<TData, any>) {
+  fetchMore(options: FetchMoreOptions<TData, any, any, any>) {
     return this.initiateFetch(this.observable.fetchMore<TData>(options));
   }
 

From 498508d9ce2786f9c6ab510914e5d078cbff57cf Mon Sep 17 00:00:00 2001
From: Lenz Weber-Tronic <lorenz.weber-tronic@apollographql.com>
Date: Wed, 18 Jun 2025 21:37:47 +0200
Subject: [PATCH 09/10] add tests

---
 src/__tests__/fetchMore.ts | 193 ++++++++++++++++++++++++++++++++++++-
 1 file changed, 192 insertions(+), 1 deletion(-)

diff --git a/src/__tests__/fetchMore.ts b/src/__tests__/fetchMore.ts
index f625283dac8..af513f5129d 100644
--- a/src/__tests__/fetchMore.ts
+++ b/src/__tests__/fetchMore.ts
@@ -223,7 +223,7 @@ describe("fetchMore on an observable query", () => {
     limit: 20,
   };
 
-  const result: any = {
+  const result: { data: TCommentData } = {
     data: {
       entry: {
         __typename: "Entry",
@@ -1667,6 +1667,197 @@ describe("fetchMore on an observable query", () => {
 
     await expect(stream).not.toEmitAnything();
   });
+
+  test("`errorPolicy` defaults to `none`", async () => {
+    const query = gql`
+      query {
+        fail
+      }
+    `;
+    const observable = setup({
+      request: { query },
+      error: new Error("This is an error"),
+    });
+    const stream = new ObservableStream(observable);
+    await expect(stream).toEmitTypedValue({
+      data: undefined,
+      dataState: "empty",
+      loading: true,
+      networkStatus: NetworkStatus.loading,
+      partial: true,
+    });
+    await expect(stream).toEmitTypedValue({
+      data: result.data,
+      dataState: "complete",
+      loading: false,
+      networkStatus: NetworkStatus.ready,
+      partial: false,
+    });
+
+    const updateQuery = jest.fn();
+    const promise = observable.fetchMore({
+      query,
+      updateQuery,
+    });
+    await expect(promise).rejects.toThrow("This is an error");
+    expect(updateQuery).not.toHaveBeenCalled();
+    await expect(stream).toEmitSimilarValue({
+      expected: (previous) => ({
+        ...previous,
+        loading: true,
+        networkStatus: NetworkStatus.fetchMore,
+      }),
+    });
+    await expect(stream).toEmitSimilarValue({
+      expected: (previous) => ({
+        ...previous,
+        loading: false,
+        networkStatus: NetworkStatus.ready,
+      }),
+    });
+    await expect(stream).not.toEmitAnything();
+  });
+
+  test("`errorPolicy` can be overwritten to `ignore`", async () => {
+    const query = gql`
+      query {
+        fail
+      }
+    `;
+    const observable = setup({
+      request: { query },
+      error: new Error("This is an error"),
+    });
+    const stream = new ObservableStream(observable);
+    await expect(stream).toEmitTypedValue({
+      data: undefined,
+      dataState: "empty",
+      loading: true,
+      networkStatus: NetworkStatus.loading,
+      partial: true,
+    });
+    await expect(stream).toEmitTypedValue({
+      data: result.data,
+      dataState: "complete",
+      loading: false,
+      networkStatus: NetworkStatus.ready,
+      partial: false,
+    });
+
+    const fallbackResult: TCommentData = {
+      entry: {
+        ...result.data.entry,
+        comments: result.data.entry.comments.concat({
+          __typename: "Comment",
+          text: "fallback comment",
+        }),
+      },
+    };
+
+    const updateQuery = jest.fn(
+      (previousResult: TCommentData): TCommentData => fallbackResult
+    );
+    const promise = observable.fetchMore({
+      query,
+      updateQuery,
+      errorPolicy: "ignore",
+    });
+    await expect(promise).resolves.toStrictEqualTyped({ data: undefined });
+    expect(updateQuery).toHaveBeenCalledTimes(1);
+    expect(updateQuery).toHaveBeenNthCalledWith(1, result.data, {
+      fetchMoreResult: undefined,
+      variables: undefined,
+    });
+    await expect(stream).toEmitSimilarValue({
+      expected: (previous) => ({
+        ...previous,
+        loading: true,
+        networkStatus: NetworkStatus.fetchMore,
+      }),
+    });
+    await expect(stream).toEmitSimilarValue({
+      expected: (previous) => ({
+        ...previous,
+        data: fallbackResult,
+        dataState: "complete",
+        loading: false,
+        networkStatus: NetworkStatus.ready,
+      }),
+    });
+    await expect(stream).not.toEmitAnything();
+  });
+
+  test("`errorPolicy` can be overwritten to `all`", async () => {
+    const query = gql`
+      query {
+        fail
+      }
+    `;
+    const observable = setup({
+      request: { query },
+      error: new Error("This is an error"),
+    });
+    const stream = new ObservableStream(observable);
+    await expect(stream).toEmitTypedValue({
+      data: undefined,
+      dataState: "empty",
+      loading: true,
+      networkStatus: NetworkStatus.loading,
+      partial: true,
+    });
+    await expect(stream).toEmitTypedValue({
+      data: result.data,
+      dataState: "complete",
+      loading: false,
+      networkStatus: NetworkStatus.ready,
+      partial: false,
+    });
+
+    const fallbackResult: TCommentData = {
+      entry: {
+        ...result.data.entry,
+        comments: result.data.entry.comments.concat({
+          __typename: "Comment",
+          text: "fallback comment",
+        }),
+      },
+    };
+
+    const updateQuery = jest.fn(
+      (previousResult: TCommentData): TCommentData => fallbackResult
+    );
+    const promise = observable.fetchMore({
+      query,
+      updateQuery,
+      errorPolicy: "all",
+    });
+    await expect(promise).resolves.toStrictEqual({
+      data: undefined,
+      error: new Error("This is an error"),
+    });
+    expect(updateQuery).toHaveBeenCalledTimes(1);
+    expect(updateQuery).toHaveBeenNthCalledWith(1, result.data, {
+      fetchMoreResult: undefined,
+      variables: undefined,
+    });
+    await expect(stream).toEmitSimilarValue({
+      expected: (previous) => ({
+        ...previous,
+        loading: true,
+        networkStatus: NetworkStatus.fetchMore,
+      }),
+    });
+    await expect(stream).toEmitSimilarValue({
+      expected: (previous) => ({
+        ...previous,
+        data: fallbackResult,
+        dataState: "complete",
+        loading: false,
+        networkStatus: NetworkStatus.ready,
+      }),
+    });
+    await expect(stream).not.toEmitAnything();
+  });
 });
 
 describe("fetchMore on an observable query with connection", () => {

From 6e67033c352486abc9f443a51d4b2cd16130e23b Mon Sep 17 00:00:00 2001
From: Lenz Weber-Tronic <lorenz.weber-tronic@apollographql.com>
Date: Wed, 18 Jun 2025 22:47:18 +0200
Subject: [PATCH 10/10] update test

---
 src/__tests__/fetchMore.ts | 38 +++++++++++++++++++++++++++++++++-----
 1 file changed, 33 insertions(+), 5 deletions(-)

diff --git a/src/__tests__/fetchMore.ts b/src/__tests__/fetchMore.ts
index af513f5129d..7f3e1f328da 100644
--- a/src/__tests__/fetchMore.ts
+++ b/src/__tests__/fetchMore.ts
@@ -3,7 +3,13 @@ import { assign, cloneDeep } from "lodash";
 import { Observable } from "rxjs";
 
 import type { TypedDocumentNode } from "@apollo/client";
-import { ApolloClient, ApolloLink, NetworkStatus, split } from "@apollo/client";
+import {
+  ApolloClient,
+  ApolloLink,
+  CombinedGraphQLErrors,
+  NetworkStatus,
+  split,
+} from "@apollo/client";
 import type {
   ApolloCache,
   FieldMergeFunction,
@@ -1795,7 +1801,14 @@ describe("fetchMore on an observable query", () => {
     `;
     const observable = setup({
       request: { query },
-      error: new Error("This is an error"),
+      result: {
+        data: {
+          entry: {
+            __typename: "Entry",
+          },
+        },
+        errors: [{ message: "This is an error" }],
+      },
     });
     const stream = new ObservableStream(observable);
     await expect(stream).toEmitTypedValue({
@@ -1832,12 +1845,27 @@ describe("fetchMore on an observable query", () => {
       errorPolicy: "all",
     });
     await expect(promise).resolves.toStrictEqual({
-      data: undefined,
-      error: new Error("This is an error"),
+      data: {
+        entry: {
+          __typename: "Entry",
+        },
+      },
+      error: new CombinedGraphQLErrors({
+        data: {
+          entry: {
+            __typename: "Entry",
+          },
+        },
+        errors: [{ message: "This is an error" }],
+      }),
     });
     expect(updateQuery).toHaveBeenCalledTimes(1);
     expect(updateQuery).toHaveBeenNthCalledWith(1, result.data, {
-      fetchMoreResult: undefined,
+      fetchMoreResult: {
+        entry: {
+          __typename: "Entry",
+        },
+      },
       variables: undefined,
     });
     await expect(stream).toEmitSimilarValue({