diff --git a/tests/scripts/all.sh b/tests/scripts/all.sh
index 6b11346..0cfb9bd 100755
--- a/tests/scripts/all.sh
+++ b/tests/scripts/all.sh
@@ -1767,6 +1767,9 @@
 
     msg "test: make, full_no_deprecated config" # ~ 5s
     make test
+
+    msg "test: ensure that X509 has no direct dependency on BIGNUM_C"
+    not grep mbedtls_mpi library/libmbedx509.a
 }
 
 component_test_full_no_deprecated_deprecated_warning () {