diff --git a/lib/libc/sys/sigqueue.2 b/lib/libc/sys/sigqueue.2
index e68a7f77f65..88346b52fd7 100644
--- a/lib/libc/sys/sigqueue.2
+++ b/lib/libc/sys/sigqueue.2
@@ -139,4 +139,7 @@ does not exist.
 The
 .Fn sigqueue
 system call conforms to
-.St -p1003.1-96 .
+.St -p1003.1-2004 
+.Sh HISTORY
+Support for POSIX realtime signal queue first appeared in
+.Fx 7.0 .
diff --git a/lib/libc/sys/timer_create.2 b/lib/libc/sys/timer_create.2
index 95ac55be435..b94e2a51f87 100644
--- a/lib/libc/sys/timer_create.2
+++ b/lib/libc/sys/timer_create.2
@@ -155,4 +155,7 @@ memory protection fault.
 The
 .Fn timer_create
 system call conforms to
-.St -p1003.1-96 .
+.St -p1003.1-2004
+.Sh HISTORY
+Support for POSIX per-process timer first appeared in
+.Fx 7.0 .
diff --git a/lib/libc/sys/timer_delete.2 b/lib/libc/sys/timer_delete.2
index f1035b888ce..97524a10063 100644
--- a/lib/libc/sys/timer_delete.2
+++ b/lib/libc/sys/timer_delete.2
@@ -72,4 +72,7 @@ is not a valid timer ID.
 The
 .Fn timer_delete
 system call conforms to
-.St -p1003.1-96 .
+.St -p1003.1-2004
+.Sh HISTORY
+Support for POSIX per-process timer first appeared in
+.Fx 7.0 .
diff --git a/lib/libc/sys/timer_settime.2 b/lib/libc/sys/timer_settime.2
index 74743b7efaa..12882df510a 100644
--- a/lib/libc/sys/timer_settime.2
+++ b/lib/libc/sys/timer_settime.2
@@ -256,4 +256,7 @@ The
 and
 .Fn timer_settime
 system calls conform to
-.St -p1003.1-96 .
+.St -p1003.1-2004
+.Sh HISTORY
+Support for POSIX per-process timer first appeared in
+.Fx 7.0 .