diff --git a/internal/gatewayapi/backendtrafficpolicy.go b/internal/gatewayapi/backendtrafficpolicy.go
index 7cc3cc5ae8..3e9a0b508b 100644
--- a/internal/gatewayapi/backendtrafficpolicy.go
+++ b/internal/gatewayapi/backendtrafficpolicy.go
@@ -263,7 +263,7 @@ func (t *Translator) processBackendTrafficPolicyForRoute(
 	// Find the Gateway that the route belongs to and add it to the
 	// gatewayRouteMap and ancestor list, which will be used to check
 	// policy overrides and populate its ancestor status.
-	parentRefs := GetParentReferences(targetedRoute)
+	parentRefs := GetManagedParentReferences(targetedRoute)
 	ancestorRefs := make([]*gwapiv1.ParentReference, 0, len(parentRefs))
 	// parentRefCtxs holds parent gateway/listener contexts for using in policy merge logic.
 	parentRefCtxs := make([]*RouteParentContext, 0, len(parentRefs))
@@ -295,12 +295,7 @@ func (t *Translator) processBackendTrafficPolicyForRoute(
 			// Do need a section name since the policy is targeting to a route.
 			ancestorRef := getAncestorRefForPolicy(mapKey.NamespacedName, p.SectionName)
 			ancestorRefs = append(ancestorRefs, &ancestorRef)
-
-			// Only process parentRefs that were handled by this translator
-			// (skip those referencing Gateways with different GatewayClasses)
-			if parentRefCtx := targetedRoute.GetRouteParentContext(p); parentRefCtx != nil {
-				parentRefCtxs = append(parentRefCtxs, parentRefCtx)
-			}
+			parentRefCtxs = append(parentRefCtxs, targetedRoute.GetRouteParentContext(p))
 		}
 	}
 
diff --git a/internal/gatewayapi/contexts.go b/internal/gatewayapi/contexts.go
index 66dbce04ba..28afe83f27 100644
--- a/internal/gatewayapi/contexts.go
+++ b/internal/gatewayapi/contexts.go
@@ -534,6 +534,22 @@ func GetParentReferences(route RouteContext) []gwapiv1.ParentReference {
 	return route.GetParentReferences()
 }
 
+// GetManagedParentReferences returns route parentRefs that are managed by this controller.
+func GetManagedParentReferences(route RouteContext) []gwapiv1.ParentReference {
+	parentRefs := GetParentReferences(route)
+	managed := make([]gwapiv1.ParentReference, 0, len(parentRefs))
+	for _, parentRef := range parentRefs {
+		// RouteParentContext is only created for parentRefs handled by this
+		// translator run. If absent, the parentRef points to a Gateway that is
+		// not managed by this controller.
+		if route.GetRouteParentContext(parentRef) == nil {
+			continue
+		}
+		managed = append(managed, parentRef)
+	}
+	return managed
+}
+
 // GetRouteStatus returns the RouteStatus object associated with the Route.
 func GetRouteStatus(route RouteContext) *gwapiv1.RouteStatus {
 	return route.GetRouteStatus()
diff --git a/internal/gatewayapi/envoyextensionpolicy.go b/internal/gatewayapi/envoyextensionpolicy.go
index 20d3201966..83ea7be986 100644
--- a/internal/gatewayapi/envoyextensionpolicy.go
+++ b/internal/gatewayapi/envoyextensionpolicy.go
@@ -200,7 +200,7 @@ func (t *Translator) processEnvoyExtensionPolicyForRoute(
 	// Find the Gateway that the route belongs to and add it to the
 	// gatewayRouteMap and ancestor list, which will be used to check
 	// policy overrides and populate its ancestor status.
-	parentRefs := GetParentReferences(targetedRoute)
+	parentRefs := GetManagedParentReferences(targetedRoute)
 	for _, p := range parentRefs {
 		if p.Kind == nil || *p.Kind == resource.KindGateway {
 			namespace := targetedRoute.GetNamespace()
diff --git a/internal/gatewayapi/securitypolicy.go b/internal/gatewayapi/securitypolicy.go
index f8f1181833..61d63cb009 100644
--- a/internal/gatewayapi/securitypolicy.go
+++ b/internal/gatewayapi/securitypolicy.go
@@ -233,7 +233,7 @@ func (t *Translator) processSecurityPolicyForRoute(
 	// Find the parent Gateways for the route and add it to the
 	// gatewayRouteMap, which will be used to check policy override.
 	// The parent gateways are also used to set the status of the policy.
-	parentRefs := GetParentReferences(targetedRoute)
+	parentRefs := GetManagedParentReferences(targetedRoute)
 	for _, p := range parentRefs {
 		if p.Kind == nil || *p.Kind == resource.KindGateway {
 			namespace := targetedRoute.GetNamespace()
diff --git a/internal/gatewayapi/securitypolicy_test.go b/internal/gatewayapi/securitypolicy_test.go
index 7967a781f3..b17cde6a81 100644
--- a/internal/gatewayapi/securitypolicy_test.go
+++ b/internal/gatewayapi/securitypolicy_test.go
@@ -884,6 +884,23 @@ func hasParentFalseCondition(p *egv1a1.SecurityPolicy) bool {
 	return false
 }
 
+func SetRouteParentContext(route RouteContext, parentRef gwapiv1.ParentReference) {
+	ctx := &RouteParentContext{ParentReference: &parentRef}
+	switch r := route.(type) {
+	case *HTTPRouteContext:
+		ctx.HTTPRoute = r.HTTPRoute
+	case *GRPCRouteContext:
+		ctx.GRPCRoute = r.GRPCRoute
+	case *TLSRouteContext:
+		ctx.TLSRoute = r.TLSRoute
+	case *TCPRouteContext:
+		ctx.TCPRoute = r.TCPRoute
+	case *UDPRouteContext:
+		ctx.UDPRoute = r.UDPRoute
+	}
+	route.SetRouteParentContext(parentRef, ctx)
+}
+
 // --- TCP branch: validateSecurityPolicyForTCP(...) returns err -> SetTranslationErrorForPolicyAncestors(...) + return
 func Test_SecurityPolicy_TCP_Invalid_setsStatus_and_returns(t *testing.T) {
 	tr := &Translator{GatewayControllerName: "gateway.envoyproxy.io/gatewayclass-controller"}
@@ -923,6 +940,7 @@ func Test_SecurityPolicy_TCP_Invalid_setsStatus_and_returns(t *testing.T) {
 			},
 		},
 	}
+	SetRouteParentContext(tcpRoute, tcpRoute.Spec.ParentRefs[0])
 
 	// Create the target reference
 	target := gwapiv1.LocalPolicyTargetReferenceWithSectionName{
@@ -1000,6 +1018,7 @@ func Test_SecurityPolicy_HTTP_Invalid_setsStatus_and_returns(t *testing.T) {
 			},
 		},
 	}
+	SetRouteParentContext(httpRoute, httpRoute.Spec.ParentRefs[0])
 
 	// Create the target reference
 	target := gwapiv1.LocalPolicyTargetReferenceWithSectionName{
diff --git a/internal/gatewayapi/testdata/securitypolicy-mixed-managed-unmanaged-route-parents.in.yaml b/internal/gatewayapi/testdata/securitypolicy-mixed-managed-unmanaged-route-parents.in.yaml
new file mode 100644
index 0000000000..7ef2349a21
--- /dev/null
+++ b/internal/gatewayapi/testdata/securitypolicy-mixed-managed-unmanaged-route-parents.in.yaml
@@ -0,0 +1,68 @@
+gateways:
+- apiVersion: gateway.networking.k8s.io/v1
+  kind: Gateway
+  metadata:
+    namespace: default
+    name: managed-gateway
+  spec:
+    gatewayClassName: envoy-gateway-class
+    listeners:
+    - name: http
+      protocol: HTTP
+      port: 80
+      allowedRoutes:
+        namespaces:
+          from: Same
+- apiVersion: gateway.networking.k8s.io/v1
+  kind: Gateway
+  metadata:
+    namespace: default
+    name: unmanaged-gateway
+  spec:
+    gatewayClassName: other-gateway-class
+    listeners:
+    - name: http
+      protocol: HTTP
+      port: 80
+      allowedRoutes:
+        namespaces:
+          from: Same
+
+httpRoutes:
+- apiVersion: gateway.networking.k8s.io/v1
+  kind: HTTPRoute
+  metadata:
+    namespace: default
+    name: mixed-parents-route
+  spec:
+    parentRefs:
+    - name: managed-gateway
+      sectionName: http
+    - name: unmanaged-gateway
+      sectionName: http
+    rules:
+    - matches:
+      - path:
+          value: "/"
+      backendRefs:
+      - name: service-1
+        port: 8080
+
+securityPolicies:
+- apiVersion: gateway.envoyproxy.io/v1alpha1
+  kind: SecurityPolicy
+  metadata:
+    namespace: default
+    name: route-policy
+  spec:
+    targetRefs:
+    - group: gateway.networking.k8s.io
+      kind: HTTPRoute
+      name: mixed-parents-route
+    authorization:
+      defaultAction: Deny
+      rules:
+      - action: Allow
+        principal:
+          clientCIDRs:
+          - 10.0.0.0/24
diff --git a/internal/gatewayapi/testdata/securitypolicy-mixed-managed-unmanaged-route-parents.out.yaml b/internal/gatewayapi/testdata/securitypolicy-mixed-managed-unmanaged-route-parents.out.yaml
new file mode 100644
index 0000000000..983f72e57b
--- /dev/null
+++ b/internal/gatewayapi/testdata/securitypolicy-mixed-managed-unmanaged-route-parents.out.yaml
@@ -0,0 +1,219 @@
+gateways:
+- apiVersion: gateway.networking.k8s.io/v1
+  kind: Gateway
+  metadata:
+    name: managed-gateway
+    namespace: default
+  spec:
+    gatewayClassName: envoy-gateway-class
+    listeners:
+    - allowedRoutes:
+        namespaces:
+          from: Same
+      name: http
+      port: 80
+      protocol: HTTP
+  status:
+    listeners:
+    - attachedRoutes: 1
+      conditions:
+      - lastTransitionTime: null
+        message: Sending translated listener configuration to the data plane
+        reason: Programmed
+        status: "True"
+        type: Programmed
+      - lastTransitionTime: null
+        message: Listener has been successfully translated
+        reason: Accepted
+        status: "True"
+        type: Accepted
+      - lastTransitionTime: null
+        message: Listener references have been resolved
+        reason: ResolvedRefs
+        status: "True"
+        type: ResolvedRefs
+      name: http
+      supportedKinds:
+      - group: gateway.networking.k8s.io
+        kind: HTTPRoute
+      - group: gateway.networking.k8s.io
+        kind: GRPCRoute
+httpRoutes:
+- apiVersion: gateway.networking.k8s.io/v1
+  kind: HTTPRoute
+  metadata:
+    name: mixed-parents-route
+    namespace: default
+  spec:
+    parentRefs:
+    - name: managed-gateway
+      sectionName: http
+    - name: unmanaged-gateway
+      sectionName: http
+    rules:
+    - backendRefs:
+      - name: service-1
+        port: 8080
+      matches:
+      - path:
+          value: /
+  status:
+    parents:
+    - conditions:
+      - lastTransitionTime: null
+        message: Route is accepted
+        reason: Accepted
+        status: "True"
+        type: Accepted
+      - lastTransitionTime: null
+        message: Resolved all the Object references for the Route
+        reason: ResolvedRefs
+        status: "True"
+        type: ResolvedRefs
+      controllerName: gateway.envoyproxy.io/gatewayclass-controller
+      parentRef:
+        name: managed-gateway
+        sectionName: http
+infraIR:
+  default/managed-gateway:
+    proxy:
+      listeners:
+      - name: default/managed-gateway/http
+        ports:
+        - containerPort: 10080
+          name: http-80
+          protocol: HTTP
+          servicePort: 80
+      metadata:
+        labels:
+          gateway.envoyproxy.io/owning-gateway-name: managed-gateway
+          gateway.envoyproxy.io/owning-gateway-namespace: default
+        ownerReference:
+          kind: GatewayClass
+          name: envoy-gateway-class
+      name: default/managed-gateway
+      namespace: envoy-gateway-system
+securityPolicies:
+- apiVersion: gateway.envoyproxy.io/v1alpha1
+  kind: SecurityPolicy
+  metadata:
+    name: route-policy
+    namespace: default
+  spec:
+    authorization:
+      defaultAction: Deny
+      rules:
+      - action: Allow
+        principal:
+          clientCIDRs:
+          - 10.0.0.0/24
+    targetRefs:
+    - group: gateway.networking.k8s.io
+      kind: HTTPRoute
+      name: mixed-parents-route
+  status:
+    ancestors:
+    - ancestorRef:
+        group: gateway.networking.k8s.io
+        kind: Gateway
+        name: managed-gateway
+        namespace: default
+        sectionName: http
+      conditions:
+      - lastTransitionTime: null
+        message: Policy has been accepted.
+        reason: Accepted
+        status: "True"
+        type: Accepted
+      controllerName: gateway.envoyproxy.io/gatewayclass-controller
+xdsIR:
+  default/managed-gateway:
+    accessLog:
+      json:
+      - path: /dev/stdout
+    globalResources:
+      proxyServiceCluster:
+        metadata:
+          kind: Service
+          name: envoy-default-managed-gateway-f4161932
+          namespace: envoy-gateway-system
+          sectionName: "8080"
+        name: default/managed-gateway
+        settings:
+        - addressType: IP
+          endpoints:
+          - host: 7.6.5.4
+            port: 8080
+            zone: zone1
+          metadata:
+            kind: Service
+            name: envoy-default-managed-gateway-f4161932
+            namespace: envoy-gateway-system
+            sectionName: "8080"
+          name: default/managed-gateway
+          protocol: TCP
+    http:
+    - address: 0.0.0.0
+      externalPort: 80
+      hostnames:
+      - '*'
+      isHTTP2: false
+      metadata:
+        kind: Gateway
+        name: managed-gateway
+        namespace: default
+        sectionName: http
+      name: default/managed-gateway/http
+      path:
+        escapedSlashesAction: UnescapeAndRedirect
+        mergeSlashes: true
+      port: 10080
+      routes:
+      - destination:
+          metadata:
+            kind: HTTPRoute
+            name: mixed-parents-route
+            namespace: default
+          name: httproute/default/mixed-parents-route/rule/0
+          settings:
+          - addressType: IP
+            endpoints:
+            - host: 7.7.7.7
+              port: 8080
+            metadata:
+              kind: Service
+              name: service-1
+              namespace: default
+              sectionName: "8080"
+            name: httproute/default/mixed-parents-route/rule/0/backend/0
+            protocol: HTTP
+            weight: 1
+        hostname: '*'
+        isHTTP2: false
+        metadata:
+          kind: HTTPRoute
+          name: mixed-parents-route
+          namespace: default
+        name: httproute/default/mixed-parents-route/rule/0/match/0/*
+        pathMatch:
+          distinct: false
+          name: ""
+          prefix: /
+        security:
+          authorization:
+            defaultAction: Deny
+            rules:
+            - action: Allow
+              name: securitypolicy/default/route-policy/authorization/rule/0
+              principal:
+                clientCIDRs:
+                - cidr: 10.0.0.0/24
+                  distinct: false
+                  ip: 10.0.0.0
+                  isIPv6: false
+                  maskLen: 24
+    readyListener:
+      address: 0.0.0.0
+      ipFamily: IPv4
+      path: /ready
+      port: 19003