diff --git a/algebra/dec_agree.v b/algebra/dec_agree.v
index 843c10767ec9265f82e1c0931226df7a72bec2f0..068ec54b1907a4413779aded2f9c2ba588ad52cf 100644
--- a/algebra/dec_agree.v
+++ b/algebra/dec_agree.v
@@ -18,7 +18,6 @@ Context {A : Type} `{∀ x y : A, Decision (x = y)}.
 
 Instance dec_agree_valid : Valid (dec_agree A) := λ x,
   if x is DecAgree _ then True else False.
-Instance dec_agree_equiv : Equiv (dec_agree A) := equivL.
 Canonical Structure dec_agreeC : cofeT := leibnizC (dec_agree A).
 
 Instance dec_agree_op : Op (dec_agree A) := λ x y,