diff --git a/src/DynareBison.yy b/src/DynareBison.yy
index 2e2087da7c814acfee1e7d1441f0047c8c871fa4..dc2d73537c2f25c2809584cec7055d2abc650d72 100644
--- a/src/DynareBison.yy
+++ b/src/DynareBison.yy
@@ -4559,6 +4559,7 @@ symbol : NAME
        | DL
        | DD
        | ADD
+       | MFS
        | MULTIPLY
        ;