diff --git a/tests/testdata/testkey_4096bits.x509.pem b/tests/testdata/testkey_4096bits.x509.pem
new file mode 100644
index 0000000..cba30d6
--- /dev/null
+++ b/tests/testdata/testkey_4096bits.x509.pem
@@ -0,0 +1,35 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----