diff --git a/lib/runtime/RefreshUtils.js b/lib/runtime/RefreshUtils.js
index 98807575..d89b5cfc 100644
--- a/lib/runtime/RefreshUtils.js
+++ b/lib/runtime/RefreshUtils.js
@@ -55,6 +55,10 @@ function getReactRefreshBoundarySignature(moduleExports) {
       continue;
     }
 
+    if (key !== 'default' && key[0] != key[0].toUpperCase()) {
+      continue;
+    }
+
     signature.push(key);
     signature.push(Refresh.getFamilyByType(moduleExports[key]));
   }
@@ -117,6 +121,11 @@ function isReactRefreshBoundary(moduleExports) {
       continue;
     }
 
+    if (key !== 'default' && key[0] != key[0].toUpperCase()) {
+      areAllExportsComponents = false;
+      continue;
+    }
+
     // We can (and have to) safely execute getters here,
     // as Webpack manually assigns harmony exports to getters,
     // without any side-effects attached.
@@ -155,6 +164,10 @@ function registerExportsForReactRefresh(moduleExports, moduleId) {
       continue;
     }
 
+    if (key !== 'default' && key[0] != key[0].toUpperCase()) {
+      continue;
+    }
+
     var exportValue = moduleExports[key];
     if (Refresh.isLikelyComponentType(exportValue)) {
       var typeID = moduleId + ' %exports% ' + key;