diff --git a/released/packages/coq-of-ocaml/coq-of-ocaml.1.1.1/opam b/released/packages/coq-of-ocaml/coq-of-ocaml.1.1.1/opam
index ac629bedb4..8cef81a387 100644
--- a/released/packages/coq-of-ocaml/coq-of-ocaml.1.1.1/opam
+++ b/released/packages/coq-of-ocaml/coq-of-ocaml.1.1.1/opam
@@ -17,7 +17,7 @@ depends: [
   "ocaml" {>= "4.02.0" & < "4.03.0"}
   "ocamlbuild" {build}
   "smart-print"
-  "yojson"
+  "yojson" {< "2.0.0"}
 ]
 tags: [
   "date:2019-05-09"