diff --git a/core/net/rpl/rpl-icmp6.c b/core/net/rpl/rpl-icmp6.c
index 8fdefdedc..c9890b706 100644
--- a/core/net/rpl/rpl-icmp6.c
+++ b/core/net/rpl/rpl-icmp6.c
@@ -64,7 +64,7 @@
 /*---------------------------------------------------------------------------*/
 #define RPL_DIO_GROUNDED                 0x80
 #define RPL_DIO_MOP_SHIFT                3
-#define RPL_DIO_MOP_MASK                 0x3c
+#define RPL_DIO_MOP_MASK                 0x38
 #define RPL_DIO_PREFERENCE_MASK          0x07
 
 #define UIP_IP_BUF       ((struct uip_ip_hdr *)&uip_buf[UIP_LLH_LEN])