diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7b76b1d4416..556e96bb9b1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,6 +13,7 @@
 * `Realm::refresh()` did not actually advance to the latest version in some cases. If there was a version newer than the current version which did not require blocking it would advance to that instead, contrary to the documented behavior.
 * Fixed `realm_query_parse_for_results` ignoring query for `query_result_t` passed as parameter ([#5841](https://github.com/realm/realm-core/pull/5841)).
 * Fixed `realm_query_parse_for_list` ignoring existing query ([#5850](https://github.com/realm/realm-core/pull/5850)).
+* Fixed not allowing asymmetric tables in partition based sync ([#5691](https://github.com/realm/realm-core/issues/5691)).
 
 ### Breaking changes
 * None.
diff --git a/src/realm.h b/src/realm.h
index 2bff945cdfd..86585fa37fe 100644
--- a/src/realm.h
+++ b/src/realm.h
@@ -122,8 +122,9 @@ typedef enum realm_value_type {
 
 typedef enum realm_schema_validation_mode {
     RLM_SCHEMA_VALIDATION_BASIC = 0,
-    RLM_SCHEMA_VALIDATION_SYNC = 1,
-    RLM_SCHEMA_VALIDATION_REJECT_EMBEDDED_ORPHANS = 2
+    RLM_SCHEMA_VALIDATION_SYNC_PBS = 1,
+    RLM_SCHEMA_VALIDATION_REJECT_EMBEDDED_ORPHANS = 2,
+    RLM_SCHEMA_VALIDATION_SYNC_FLX = 4
 } realm_schema_validation_mode_e;
 
 /**
diff --git a/src/realm/object-store/c_api/schema.cpp b/src/realm/object-store/c_api/schema.cpp
index efa4fbfca72..6c80dc5fca5 100644
--- a/src/realm/object-store/c_api/schema.cpp
+++ b/src/realm/object-store/c_api/schema.cpp
@@ -58,7 +58,7 @@ RLM_API uint64_t realm_get_schema_version(const realm_t* realm)
 RLM_API bool realm_schema_validate(const realm_schema_t* schema, uint64_t validation_mode)
 {
     return wrap_err([&]() {
-        schema->ptr->validate(validation_mode);
+        schema->ptr->validate(static_cast<SchemaValidationMode>(validation_mode));
         return true;
     });
 }
diff --git a/src/realm/object-store/object_schema.cpp b/src/realm/object-store/object_schema.cpp
index 15909958015..512f47eb521 100644
--- a/src/realm/object-store/object_schema.cpp
+++ b/src/realm/object-store/object_schema.cpp
@@ -329,7 +329,7 @@ static void validate_property(Schema const& schema, ObjectSchema const& parent_o
 }
 
 void ObjectSchema::validate(Schema const& schema, std::vector<ObjectSchemaValidationException>& exceptions,
-                            bool for_sync) const
+                            SchemaValidationMode validation_mode) const
 {
     std::vector<StringData> public_property_names;
     std::vector<StringData> internal_property_names;
@@ -416,6 +416,8 @@ void ObjectSchema::validate(Schema const& schema, std::vector<ObjectSchemaValida
         exceptions.emplace_back("Specified primary key '%1.%2' does not exist.", name, primary_key);
     }
 
+    auto for_sync =
+        (validation_mode & SchemaValidationMode::SyncPBS) || (validation_mode & SchemaValidationMode::SyncFLX);
     if (for_sync && table_type != ObjectSchema::ObjectType::Embedded) {
         if (primary_key.empty()) {
             exceptions.emplace_back(util::format("There must be a primary key property named '_id' on a synchronized "
@@ -432,6 +434,12 @@ void ObjectSchema::validate(Schema const& schema, std::vector<ObjectSchemaValida
     if (!for_sync && table_type == ObjectSchema::ObjectType::TopLevelAsymmetric) {
         exceptions.emplace_back(util::format("Asymmetric table '%1' not allowed in a local Realm", name));
     }
+
+    auto pbs_sync =
+        (validation_mode & SchemaValidationMode::SyncPBS) && !(validation_mode & SchemaValidationMode::SyncFLX);
+    if (pbs_sync && table_type == ObjectSchema::ObjectType::TopLevelAsymmetric) {
+        exceptions.emplace_back(util::format("Asymmetric table '%1' not allowed in partition based sync", name));
+    }
 }
 
 namespace realm {
diff --git a/src/realm/object-store/object_schema.hpp b/src/realm/object-store/object_schema.hpp
index 69bc5783fd1..e0a6861cc7c 100644
--- a/src/realm/object-store/object_schema.hpp
+++ b/src/realm/object-store/object_schema.hpp
@@ -32,6 +32,7 @@ class Table;
 enum class PropertyType : unsigned short;
 struct ObjectSchemaValidationException;
 struct Property;
+enum SchemaValidationMode : uint64_t;
 
 class ObjectSchema {
 public:
@@ -80,7 +81,7 @@ class ObjectSchema {
     bool property_is_computed(Property const& property) const noexcept;
 
     void validate(Schema const& schema, std::vector<ObjectSchemaValidationException>& exceptions,
-                  bool for_sync) const;
+                  SchemaValidationMode validation_mode) const;
 
     friend bool operator==(ObjectSchema const& a, ObjectSchema const& b) noexcept;
 
diff --git a/src/realm/object-store/schema.cpp b/src/realm/object-store/schema.cpp
index ec5c37e47c4..eff678472d6 100644
--- a/src/realm/object-store/schema.cpp
+++ b/src/realm/object-store/schema.cpp
@@ -190,7 +190,7 @@ std::unordered_set<std::string> get_embedded_object_orphans(const Schema& schema
 
 } // end anonymous namespace
 
-void Schema::validate(uint64_t validation_mode) const
+void Schema::validate(SchemaValidationMode validation_mode) const
 {
     std::vector<ObjectSchemaValidationException> exceptions;
 
@@ -206,9 +206,8 @@ void Schema::validate(uint64_t validation_mode) const
             ObjectSchemaValidationException("Type '%1' appears more than once in the schema.", it->name));
     }
 
-    const bool for_sync = validation_mode & SchemaValidationMode::Sync;
     for (auto const& object : *this) {
-        object.validate(*this, exceptions, for_sync);
+        object.validate(*this, exceptions, validation_mode);
     }
 
     // TODO: remove this client side check once the server supports it
diff --git a/src/realm/object-store/schema.hpp b/src/realm/object-store/schema.hpp
index e73d3de5be5..44522882eeb 100644
--- a/src/realm/object-store/schema.hpp
+++ b/src/realm/object-store/schema.hpp
@@ -31,7 +31,7 @@ class StringData;
 struct TableKey;
 struct Property;
 
-enum SchemaValidationMode : uint64_t { Basic = 0, Sync = 1, RejectEmbeddedOrphans = 2 };
+enum SchemaValidationMode : uint64_t { Basic = 0, SyncPBS = 1, RejectEmbeddedOrphans = 2, SyncFLX = 4 };
 
 // How to handle update_schema() being called on a file which has
 // already been initialized with a different schema
@@ -147,7 +147,7 @@ class Schema : private std::vector<ObjectSchema> {
 
     // Verify that this schema is internally consistent (i.e. all properties are
     // valid, links link to types that actually exist, etc.)
-    void validate(uint64_t validation_mode = SchemaValidationMode::Basic) const;
+    void validate(SchemaValidationMode validation_mode = SchemaValidationMode::Basic) const;
 
     // Get the changes which must be applied to this schema to produce the passed-in schema
     std::vector<SchemaChange> compare(Schema const&, SchemaMode = SchemaMode::Automatic,
diff --git a/src/realm/object-store/shared_realm.cpp b/src/realm/object-store/shared_realm.cpp
index d700f0de382..736bfe96a27 100644
--- a/src/realm/object-store/shared_realm.cpp
+++ b/src/realm/object-store/shared_realm.cpp
@@ -385,14 +385,17 @@ void Realm::update_schema(Schema schema, uint64_t version, MigrationFunction mig
                           DataInitializationFunction initialization_function, bool in_transaction)
 {
     uint64_t validation_mode = SchemaValidationMode::Basic;
-    if (m_config.sync_config) {
-        validation_mode |= SchemaValidationMode::Sync;
+#if REALM_ENABLE_SYNC
+    if (auto sync_config = m_config.sync_config) {
+        validation_mode |=
+            sync_config->flx_sync_requested ? SchemaValidationMode::SyncFLX : SchemaValidationMode::SyncPBS;
     }
+#endif
     if (m_config.schema_mode == SchemaMode::AdditiveExplicit) {
         validation_mode |= SchemaValidationMode::RejectEmbeddedOrphans;
     }
 
-    schema.validate(validation_mode);
+    schema.validate(static_cast<SchemaValidationMode>(validation_mode));
 
     bool was_in_read_transaction = is_in_read_transaction();
     Schema actual_schema = get_full_schema();
diff --git a/test/object-store/schema.cpp b/test/object-store/schema.cpp
index 33846e3920e..58268e213d4 100644
--- a/test/object-store/schema.cpp
+++ b/test/object-store/schema.cpp
@@ -372,7 +372,8 @@ TEST_CASE("Schema") {
                  ObjectSchema::ObjectType::TopLevelAsymmetric,
                  {{"_id", PropertyType::Int, Property::IsPrimary{true}}, {"street", PropertyType::String}}},
             };
-            REQUIRE_NOTHROW(schema.validate(SchemaValidationMode::Sync));
+            REQUIRE_NOTHROW(schema.validate(SchemaValidationMode::SyncFLX));
+            REQUIRE_THROWS(schema.validate(SchemaValidationMode::SyncPBS));
         }
 
         SECTION("asymmetric tables not allowed in local realm") {
@@ -392,7 +393,7 @@ TEST_CASE("Schema") {
                  {{"_id", PropertyType::Int, Property::IsPrimary{true}}}},
             };
             REQUIRE_THROWS_CONTAINING(
-                schema.validate(SchemaValidationMode::Sync),
+                schema.validate(SchemaValidationMode::SyncFLX),
                 "Property 'object.link' of type 'object' cannot be a link to an asymmetric object.");
         }
 
@@ -403,7 +404,7 @@ TEST_CASE("Schema") {
                  {{"link", PropertyType::Object | PropertyType::Nullable, "link target"}}},
                 {"link target", {{"value", PropertyType::Int}}},
             };
-            REQUIRE_THROWS_CONTAINING(schema.validate(SchemaValidationMode::Sync),
+            REQUIRE_THROWS_CONTAINING(schema.validate(SchemaValidationMode::SyncFLX),
                                       "Asymmetric table with property 'object.link' of type 'object' cannot have a "
                                       "non-embedded object type.");
         }
@@ -416,7 +417,7 @@ TEST_CASE("Schema") {
                   {"link", PropertyType::Object | PropertyType::Nullable, "link target"}}},
                 {"link target", ObjectSchema::ObjectType::Embedded, {{"value", PropertyType::Int}}},
             };
-            schema.validate(SchemaValidationMode::Sync);
+            schema.validate(SchemaValidationMode::SyncFLX);
         }
 
         SECTION("rejects array properties with no target object") {
diff --git a/test/object-store/sync/flx_sync.cpp b/test/object-store/sync/flx_sync.cpp
index 4fa4432ce23..6caba2d9693 100644
--- a/test/object-store/sync/flx_sync.cpp
+++ b/test/object-store/sync/flx_sync.cpp
@@ -1950,6 +1950,21 @@ TEST_CASE("flx: asymmetric sync", "[sync][flx][app]") {
         });
     }
 
+    SECTION("asymmetric table not allowed in PBS") {
+        Schema schema{
+            {"Asymmetric2",
+             ObjectSchema::ObjectType::TopLevelAsymmetric,
+             {
+                 {"_id", PropertyType::Int, Property::IsPrimary{true}},
+                 {"location", PropertyType::Int},
+                 {"reading", PropertyType::Int},
+             }},
+        };
+
+        SyncTestFile config(harness->app(), bson::Bson{}, schema);
+        REQUIRE_THROWS(Realm::get_shared_realm(config));
+    }
+
     // Add any new test sections above this point
 
     SECTION("teardown") {