diff --git a/Cargo.toml b/Cargo.toml
index d852f17a7..e0ba03e6a 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -39,7 +39,7 @@ crossbeam-channel = "0.2"
 futures = "0.1"
 futures-cpupool = "0.1"
 error-chain = "0.8"
-owning_ref = "0.3"
+owning_ref = "0.4"
 stable_deref_trait = "1.0.0"
 rust-stemmers = "1"
 downcast = { version="0.9" }