diff --git a/src/mathed/InsetMathCases.cpp b/src/mathed/InsetMathCases.cpp
index 480b69d247..317c584907 100644
--- a/src/mathed/InsetMathCases.cpp
+++ b/src/mathed/InsetMathCases.cpp
@@ -72,12 +72,14 @@ void InsetMathCases::doDispatch(Cursor & cur, FuncRequest & cmd)
 	//lyxerr << "*** InsetMathCases: request: " << cmd << endl;
 	switch (cmd.action) {
 	case LFUN_TABULAR_FEATURE: {
-		cur.recordUndo();
 		docstring const & s = cmd.argument();
-		if (s == "add-vline-left" || s == "add-vline-right") {
+		// vertical lines and adding/deleting columns is not allowed for \cases
+		if (s == "append-column" || s == "delete-column"
+			|| s == "add-vline-left" || s == "add-vline-right") {
 			cur.undispatched();
 			break;
 		}
+		cur.recordUndo();
 	}
 	default:
 		InsetMathGrid::doDispatch(cur, cmd);
@@ -98,6 +100,14 @@ bool InsetMathCases::getStatus(Cursor & cur, FuncRequest const & cmd,
 				s));
 			return true;
 		}
+		if (s == "append-column" || s == "delete-column") {
+			flag.setEnabled(false);
+			flag.message(bformat(
+				from_utf8(N_("Changing number of columns not allowed in\
+							 'cases': feature %1$s")),
+				s));
+			return true;
+		}
 	}
 	default:
 		return InsetMathGrid::getStatus(cur, cmd, flag);