diff --git a/java/client/src/org/openqa/selenium/remote/codec/w3c/W3CHttpCommandCodec.java b/java/client/src/org/openqa/selenium/remote/codec/w3c/W3CHttpCommandCodec.java
index 341eaeaf72c85..374627842bca2 100644
--- a/java/client/src/org/openqa/selenium/remote/codec/w3c/W3CHttpCommandCodec.java
+++ b/java/client/src/org/openqa/selenium/remote/codec/w3c/W3CHttpCommandCodec.java
@@ -70,6 +70,7 @@
 import com.google.common.collect.ImmutableMap;
 import com.google.common.io.Resources;
 
+import org.openqa.selenium.InvalidSelectorException;
 import org.openqa.selenium.WebDriverException;
 import org.openqa.selenium.interactions.Interaction;
 import org.openqa.selenium.interactions.KeyInput;
@@ -187,6 +188,9 @@ public W3CHttpCommandCodec() {
 
         switch (using) {
           case "class name":
+            if (value.matches(".*\\s.*")) {
+              throw new InvalidSelectorException("Compound class names not permitted");
+            }
             toReturn.put("using", "css selector");
             toReturn.put("value", "." + cssEscape(value));
             break;
diff --git a/java/client/test/org/openqa/selenium/ElementFindingTest.java b/java/client/test/org/openqa/selenium/ElementFindingTest.java
index 4a3345b1e29a8..3542355f5c7c6 100644
--- a/java/client/test/org/openqa/selenium/ElementFindingTest.java
+++ b/java/client/test/org/openqa/selenium/ElementFindingTest.java
@@ -347,9 +347,6 @@ public void testFindingASingleElementByCompoundClassNameShouldThrow() {
   }
 
   @Test
-  @NotYetImplemented(MARIONETTE)
-  @NotYetImplemented(SAFARI)
-  @NotYetImplemented(EDGE)
   public void testFindingMultipleElementsByCompoundClassNameShouldThrow() {
     driver.get(pages.xhtmlTestPage);
     assertThatExceptionOfType(NoSuchElementException.class)