diff --git a/src/test_certs_r3.sh b/src/test_certs_r3.sh
index 9da25cd9..6088dc82 100755
--- a/src/test_certs_r3.sh
+++ b/src/test_certs_r3.sh
@@ -17,7 +17,7 @@ test_ta () {
     ossl_status=$?
 
     # log it to file and to stdout
-    echo "$ossl_output" > ${outputdir}/oqs.log
+    echo "$ossl_output" >> ${outputdir}/oqs.log
     echo "$ossl_output"