--- a/spec/latest/json-ld-api/index.html	Sat Dec 22 13:48:23 2012 -0500
+++ b/spec/latest/json-ld-api/index.html	Sat Dec 22 15:08:25 2012 -0500
@@ -801,6 +801,10 @@
                otherwise set it to the result of expanding <em>property</em> according to the steps
                outlined in <a href="#iri-expansion">IRI Expansion</a> (passing <code>true</code> for
                the <em>vocabRelative</em> flag).</li>
+            <li>If <em>expanded property</em> is <tref>null</tref>, skip the 
+              current <em>property</em>-<em>value</em> pair and continue to the
+              next <em>property</em>-<em>value</em> pair in <em>element</em>.
+            </li>
             <li>If <em>expanded property</em> is a <tref>keyword</tref>, process it as
               follows:
               <ol class="algorithm">
@@ -1121,7 +1125,8 @@
       </ol>
     </li>
     <li>If an <tref>IRI mapping</tref> exists for <em>value</em> in the <tref>active context</tref>
-      that is not a <tref>property generator</tref> return its <tref>IRI</tref>.</li>
+      that is not a <tref>property generator</tref> return the value of the
+      <tref>IRI mapping</tref>.</li>
     <li>If <em>value</em> contains a colon (<code>:</code>), perform the following steps:
       <ol class="algorithm">
         <li>Split <em>value</em> into a <em>prefix</em> and <em>suffix</em> at the first occurrence of