diff --git a/include/ntapi/nt_process.h b/include/ntapi/nt_process.h
index d7a4831..092a95e 100644
--- a/include/ntapi/nt_process.h
+++ b/include/ntapi/nt_process.h
@@ -186,6 +186,7 @@ typedef enum _nt_process_create_info_class {
 #define NT_PROCESS_GUID_NTPGRP		{0xfa383cc0,0xa25b,0x4448,{0x83,0x45,0x51,0x45,0x4d,0xa8,0x2f,0x30}}
 #define NT_PROCESS_GUID_PIDMAP		{0xba054c90,0x8b4f,0x4989,{0xa0,0x52,0x32,0xce,0x41,0x9e,0xbf,0x97}}
 #define NT_PROCESS_GUID_PIDANY		{0x431bf6a6,0x65c4,0x4eb0,{0x88,0xca,0x16,0xfe,0xc0,0x18,0xc8,0xb7}}
+#define NT_PROCESS_GUID_NTPIPC		{0xc37f1735,0x693d,0x4695,{0xbc,0x54,0x03,0xfd,0xa2,0x7d,0x43,0x0a}}
 
 /* friendly process object directory prefixes */
 #define NT_PROCESS_OBJDIR_PREFIX_NTPGRP	{'n','t','p','g','r','p'}