diff --git a/cellarium/cas/resources/feedback_template.html b/cellarium/cas/resources/feedback_template.html
index 5e57e81..495c9e2 100644
--- a/cellarium/cas/resources/feedback_template.html
+++ b/cellarium/cas/resources/feedback_template.html
@@ -1,6 +1,6 @@
 <div>
   <hr/>
   <p>We're happy that you are using the Cell Annotation Service! We'd love to hear about your experience and how we can improve.</p>
-  <p><a href={link} target="_blank">Please click here to provide feedback!</a></p>
+  <p><a href={link} target="_blank" rel="noopener">Please click here to provide feedback!</a></p>
   <hr/>
 </div>
\ No newline at end of file
diff --git a/cellarium/cas/resources/low_quota_feedback_template.html b/cellarium/cas/resources/low_quota_feedback_template.html
index 16f82b9..e357c62 100644
--- a/cellarium/cas/resources/low_quota_feedback_template.html
+++ b/cellarium/cas/resources/low_quota_feedback_template.html
@@ -2,6 +2,6 @@
     <hr/>
     <p>Thank you for using CAS! Please note that you have {remaining_quota} cells remaining in your quota during the beta testing phase.</p>
     <p>We'd love to hear your feedback on your experience so far and how we can improve the service. As a token of appreciation, we will extend your free quota to 200,000 cells as soon as we receive your input.</p>
-    <p><a href={link} target="_blank">Please click here to provide feedback.</a></p>
+    <p><a href={link} target="_blank" rel="noopener">Please click here to provide feedback.</a></p>
     <hr/>
 </div>
\ No newline at end of file