diff --git a/Changelog.md b/Changelog.md
--- a/Changelog.md
+++ b/Changelog.md
@@ -1,5 +1,8 @@
 # Changelog for `proto-lens-runtime`
 
+## v0.4.0.1
+- Remove an obsolete dependency on `data-default-class`.
+
 ## v0.4.0.0
 - Split out from `proto-lens-protoc`.
 - Use simplified lens-labels instances. (#208)
diff --git a/proto-lens-runtime.cabal b/proto-lens-runtime.cabal
--- a/proto-lens-runtime.cabal
+++ b/proto-lens-runtime.cabal
@@ -2,10 +2,10 @@
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 6f3d113eb5e7a24246b7511da1032022b63c39a76df5616230792fb12b94bafa
+-- hash: 3622c56080cb91315aba6bffa02e3ba8c2662441b32aabfd2b983bb32399b9ad
 
 name:           proto-lens-runtime
-version:        0.4.0.0
+version:        0.4.0.1
 description:    Modules that are needed by the Haskell files generated by proto-lens-protoc. For forwards compatibility, we reexport them as new module names so that other packages don't accidentally write non-generated code that relies on these modules being reexported by this package.
 homepage:       https://github.com/google/proto-lens#readme
 bug-reports:    https://github.com/google/proto-lens/issues
@@ -48,7 +48,6 @@
       base >=4.9 && <4.12
     , bytestring ==0.10.*
     , containers ==0.5.*
-    , data-default-class >=0.0 && <0.2
     , deepseq ==1.4.*
     , filepath >=1.4 && <1.6
     , lens-family ==1.2.*