diff --git a/rocq-brick-libstdcpp/proof/mutex/demo_cpp_proof.v b/rocq-brick-libstdcpp/proof/mutex/demo_cpp_proof.v
index b8e21bc..8a0268c 100644
--- a/rocq-brick-libstdcpp/proof/mutex/demo_cpp_proof.v
+++ b/rocq-brick-libstdcpp/proof/mutex/demo_cpp_proof.v
@@ -34,7 +34,7 @@ Definition P `{Σ : cpp_logic, σ : genv} (this : ptr) : TT -t> mpred :=
 
 sl.lock
 Definition CR
-    `{Σ : cpp_logic, σ : genv, HasOwn mpredI recursive_mutex.cmraR}
+    `{Σ : cpp_logic, σ : genv, HasOwn (iPropI _) recursive_mutex.cmraR}
     (γ : recursive_mutex.rmutex_gname) (q : cQp.t) : Rep :=
   structR "C" q **
   _field "C::mut" |-> recursive_mutex.R γ.(recursive_mutex.lock_gname) q **
@@ -48,7 +48,7 @@ Section recursive_mutex.
   Import recursive_mutex.
   Context `{Σ : cpp_logic, σ : genv}.
   Context {HAS_THREADS : HasStdThreads Σ}.
-  Context {has_rmutex : HasOwn mpredI recursive_mutex.cmraR}.
+  Context {has_rmutex : HasOwn (iPropI _) recursive_mutex.cmraR}.
 
   Lemma acquireable_update_equiv {TT : tele} γ th f t1 t2 P :
     acquire t1 t2 ->
@@ -65,7 +65,7 @@ End recursive_mutex.
 Section with_cpp.
   Context `{Σ : cpp_logic, σ : genv}.
   Context {HAS_THREADS : HasStdThreads Σ}.
-  Context {has_rmutex : HasOwn mpredI recursive_mutex.cmraR}.
+  Context {has_rmutex : HasOwn (iPropI _) recursive_mutex.cmraR}.
 
   #[global] Instance: LearnEq2 CR'.
   Proof. solve_learnable. Qed.
diff --git a/rocq-brick-libstdcpp/proof/mutex/spec.v b/rocq-brick-libstdcpp/proof/mutex/spec.v
index 36db896..283336f 100644
--- a/rocq-brick-libstdcpp/proof/mutex/spec.v
+++ b/rocq-brick-libstdcpp/proof/mutex/spec.v
@@ -100,11 +100,6 @@ Section with_cpp.
 End with_cpp.
 End mutex.
 
-(* TODO upstream *)
-#[global] Declare Instance
-  own_WeaklyObjective `{Σ : cpp_logic} {A : cmra} `{!HasOwn mpredI A} γ (a : A)  :
-  WeaklyObjective (PROP := iPropI _) (own γ a).
-
 Module recursive_mutex.
 
   (** <<locked γ th n>> <<th>> owns the mutex <<γ>> <<n>> times. *)
@@ -124,7 +119,7 @@ Module recursive_mutex.
   Canonical Structure cmraR := (excl_authR (prodO natO thread_idTO)).
 
   sl.lock
-  Definition inv_rmutex `{Σ : cpp_logic} `{!HasOwn mpredI cmraR} (g : rmutex_gname) (P : mpred) : mpred :=
+  Definition inv_rmutex `{Σ : cpp_logic} `{!HasOwn (iPropI _) cmraR} (g : rmutex_gname) (P : mpred) : mpred :=
     inv rmutex_namespace
       (Exists n th, own g.(level_gname) (●E (n, th)) **
         match n with
@@ -172,7 +167,7 @@ Module recursive_mutex.
     end.
 
   sl.lock
-  Definition acquireable `{Σ : cpp_logic, !HasStdThreads Σ, !HasOwn mpredI cmraR} (g : rmutex_gname) (th : thread_idT) {TT: tele} (t : acquire_state TT) (P : TT -t> mpred) : mpred :=
+  Definition acquireable `{Σ : cpp_logic, !HasStdThreads Σ, !HasOwn (iPropI _) cmraR} (g : rmutex_gname) (th : thread_idT) {TT: tele} (t : acquire_state TT) (P : TT -t> mpred) : mpred :=
     current_thread th **
     match t with
     | NotHeld => locked g.(lock_gname) th 0
@@ -188,7 +183,7 @@ Module recursive_mutex.
     Axiom locked_excl_different_thread : forall g th th' n m,
       locked g th n ** locked g th' m |-- [| n = 0 \/ m = 0 |] ** True.
 
-    Context `{!HasOwn mpredI cmraR, !HasStdThreads Σ}.
+    Context `{!HasOwn (iPropI _) cmraR, !HasStdThreads Σ}.
 
     #[global] Instance acquireable_learn γ th TT : LearnEq2 (acquireable γ th (TT := TT)).
     Proof. solve_learnable. Qed.
@@ -297,7 +292,7 @@ Section with_cpp.
     - exists (S n). naive_solver.
   Qed.
 
-  Context `{!HasOwn mpredI cmraR}.
+  Context `{!HasOwn (iPropI _) cmraR}.
 
   #[program]
   Definition acquireable_is_acquired_C {TT} g th t t' P