diff --git a/util/plugins/eu.esdihumboldt.util.groovy.sandbox/src/eu/esdihumboldt/util/groovy/sandbox/internal/RestrictiveGroovyInterceptor.java b/util/plugins/eu.esdihumboldt.util.groovy.sandbox/src/eu/esdihumboldt/util/groovy/sandbox/internal/RestrictiveGroovyInterceptor.java
index 92130e60ce..3aa23e30b1 100644
--- a/util/plugins/eu.esdihumboldt.util.groovy.sandbox/src/eu/esdihumboldt/util/groovy/sandbox/internal/RestrictiveGroovyInterceptor.java
+++ b/util/plugins/eu.esdihumboldt.util.groovy.sandbox/src/eu/esdihumboldt/util/groovy/sandbox/internal/RestrictiveGroovyInterceptor.java
@@ -49,6 +49,7 @@
 import java.util.Set;
 import java.util.TreeMap;
 import java.util.UUID;
+import java.util.regex.Pattern;
 
 import org.codehaus.groovy.runtime.GStringImpl;
 import org.codehaus.groovy.runtime.InvokerHelper;
@@ -146,6 +147,9 @@ public class RestrictiveGroovyInterceptor extends GroovyInterceptor {
 		allowedClasses.add(TextStyle.class);
 		allowedClasses.add(SignStyle.class);
 
+		// regular expressions
+		allowedClasses.add(Pattern.class);
+
 		// helper classes
 		allowedClasses.add(SimpleDateFormat.class);
 		allowedClasses.add(UUID.class);