diff --git a/src/machine.adoc b/src/machine.adoc
index a7690dc01..2b056fcd9 100644
--- a/src/machine.adoc
+++ b/src/machine.adoc
@@ -1815,6 +1815,15 @@ other instruction address exceptions.
 
 [NOTE]
 ====
+A Software Check exception is a synchronous exception that is triggered when
+there are violations of checks and assertions defined by ISA extensions that
+aim to safeguard the integrity of software assets, including e.g. control-flow
+and memory-access constraints. When this exception is raised, the `__x__tval`
+register is set either to 0 or to an informative value defined by the extension
+that stipulated the exception be raised.  The priority of this exception,
+relative to other synchronous exceptions, depends on the cause of this exception
+and is defined by the extension that stipulated the exception be raised.
+
 A Hardware Error exception is a synchronous exception triggered when corrupted or
 uncorrectable data is accessed explicitly or implicitly by an instruction.  In
 this context, "data" encompasses all types of information used within a RISC-V