diff --git a/codec-http/src/main/java/io/netty/handler/codec/http/HttpVersion.java b/codec-http/src/main/java/io/netty/handler/codec/http/HttpVersion.java
index 26be9ebe62..0dbfda8ec0 100644
--- a/codec-http/src/main/java/io/netty/handler/codec/http/HttpVersion.java
+++ b/codec-http/src/main/java/io/netty/handler/codec/http/HttpVersion.java
@@ -71,18 +71,9 @@ public class HttpVersion implements Comparable<HttpVersion> {
         // * http://trac.tools.ietf.org/wg/httpbis/trac/ticket/1
         // * http://trac.tools.ietf.org/wg/httpbis/trac/wiki
         //
-        // TODO: Remove the uppercase conversion in 4.1.0 as the RFC state it must be HTTP (uppercase)
-        //       See https://github.com/netty/netty/issues/1682
-
         HttpVersion version = version0(text);
         if (version == null) {
-            text = text.toUpperCase();
-            // try again after convert to uppercase
-            version = version0(text);
-            if (version == null) {
-                // still no match, construct a new one
-                version = new HttpVersion(text, true);
-            }
+            version = new HttpVersion(text, true);
         }
         return version;
     }