diff --git a/plugins/out_s3/s3_multipart.c b/plugins/out_s3/s3_multipart.c
index 7ad7b2095b1..20711b4232a 100644
--- a/plugins/out_s3/s3_multipart.c
+++ b/plugins/out_s3/s3_multipart.c
@@ -652,7 +652,8 @@ flb_sds_t get_etag(char *response, size_t size)
         return NULL;
     }
 
-    tmp = strstr(response, "ETag:");
+    //tmp = strstr(response, "ETag:");
+    tmp = strcasestr(response, "ETag:");
     if (!tmp) {
         return NULL;
     }