diff --git a/core/validatorapi/teku.go b/core/validatorapi/teku.go
index 5dba82f97..d3a0d173f 100644
--- a/core/validatorapi/teku.go
+++ b/core/validatorapi/teku.go
@@ -32,7 +32,7 @@ type TekuProposerConfig struct {
 
 type TekuBuilder struct {
 	Enabled   bool              `json:"enabled"`
-	Overrides map[string]string `json:"registration_overrides"`
+	Overrides map[string]string `json:"registration_overrides,omitempty"`
 }
 
 const dead = "0x000000000000000000000000000000000000dead"