diff --git a/src/b-st-ext.adoc b/src/b-st-ext.adoc
index 9b73fbc19..7f239781d 100644
--- a/src/b-st-ext.adoc
+++ b/src/b-st-ext.adoc
@@ -191,7 +191,7 @@ along with their specific mapping:
 
 |✓
 |✓
-|orc.b _rd_, _rs1_, _rs2_
+|orc.b _rd_, _rs_
 |<<#insns-orc_b>>
 |
 |&#10003;