diff --git a/fauxflake-core/src/main/java/com/github/rholder/fauxflake/util/MacUtils.java b/fauxflake-core/src/main/java/com/github/rholder/fauxflake/util/MacUtils.java
index 0d2f3e8..aad8e51 100644
--- a/fauxflake-core/src/main/java/com/github/rholder/fauxflake/util/MacUtils.java
+++ b/fauxflake-core/src/main/java/com/github/rholder/fauxflake/util/MacUtils.java
@@ -92,8 +92,15 @@ public static byte[] realMacAddress() {
      * Optionally setting the system property OVERRIDE_MAC_PROP to a valid MAC
      * address will result in it being returned instead.
      */
-    public static byte[] macAddress() {
+public static byte[] macAddress() {
         byte[] override = getOverride();
-        return  override != null ? override : realMacAddress();
+
+        if (override == null)
+            override = realMacAddress();
+
+        // lop off unicast/multicast lower bit to preserve top vendor bit & resolution. This
+        override[0] = (byte)((short)(override[0] & 0xff) >> 1);
+
+        return override;
     }
 }
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