Index: validator/spec/html5.html
===================================================================
--- validator/spec/html5.html	(revision 338)
+++ validator/spec/html5.html	(working copy)
@@ -10631,8 +10631,8 @@
    <dd>Empty.</dd>
    <dt>Content attributes:</dt>
    <dd><a href=#global-attributes>Global attributes</a></dd>
-   <dd><code title=attr-link-href><a href=#attr-link-href>href</a></code></dd>
-   <dd><code title=attr-link-rel><a href=#attr-link-rel>rel</a></code></dd>
+   <dd><code title=attr-link-href><a href=#attr-link-href>href</a></code> <span>(required)</span></dd>
+   <dd><code title=attr-link-rel><a href=#attr-link-rel>rel</a></code> <span>(required)</span></dd>
    <dd><code title=attr-link-media><a href=#attr-link-media>media</a></code></dd>
    <dd><code title=attr-link-hreflang><a href=#attr-link-hreflang>hreflang</a></code></dd>
    <dd><code title=attr-link-type><a href=#attr-link-type>type</a></code></dd>
@@ -18689,7 +18689,7 @@
    <dt>Content attributes:</dt>
    <dd><a href=#global-attributes>Global attributes</a></dd>
    <dd><code title=attr-img-alt><a href=#attr-img-alt>alt</a></code></dd>
-   <dd><code title=attr-img-src><a href=#attr-img-src>src</a></code></dd>
+   <dd><code title=attr-img-src><a href=#attr-img-src>src</a></code> <span>(required)</span></dd>
    <dd><code title=attr-hyperlink-usemap><a href=#attr-hyperlink-usemap>usemap</a></code></dd>
    <dd><code title=attr-img-ismap><a href=#attr-img-ismap>ismap</a></code></dd>
    <dd><code title=attr-dim-width><a href=#attr-dim-width>width</a></code></dd>
@@ -20867,8 +20867,8 @@
    <dd>Zero or more <code><a href=#the-param-element>param</a></code> elements, then, <a href=#transparent>transparent</a>.</dd>
    <dt>Content attributes:</dt>
    <dd><a href=#global-attributes>Global attributes</a></dd>
-   <dd><code title=attr-object-data><a href=#attr-object-data>data</a></code></dd>
-   <dd><code title=attr-object-type><a href=#attr-object-type>type</a></code></dd>
+   <dd><code title=attr-object-data><a href=#attr-object-data>data</a></code> <span>(required, if the <code title=attr-object-type><a href=#attr-object-type>type</a></code> attribute is not present)</span></dd>
+   <dd><code title=attr-object-type><a href=#attr-object-type>type</a></code> <span>(required, if the <code title=attr-object-data><a href=#attr-object-data>data</a></code> attribute is not present)</span></dd>
    <dd><code title=attr-object-name><a href=#attr-object-name>name</a></code></dd>
    <dd><code title=attr-hyperlink-usemap><a href=#attr-hyperlink-usemap>usemap</a></code></dd>
    <dd><code title=attr-fae-form><a href=#attr-fae-form>form</a></code></dd>
@@ -21401,8 +21401,8 @@
    <dd>Empty.</dd>
    <dt>Content attributes:</dt>
    <dd><a href=#global-attributes>Global attributes</a></dd>
-   <dd><code title=attr-param-name><a href=#attr-param-name>name</a></code></dd>
-   <dd><code title=attr-param-value><a href=#attr-param-value>value</a></code></dd>
+   <dd><code title=attr-param-name><a href=#attr-param-name>name</a></code> <span>(required)</span></dd>
+   <dd><code title=attr-param-value><a href=#attr-param-value>value</a></code> <span>(required)</span></dd>
    <dt>DOM interface:</dt>
    <dd>
 <pre class=idl>interface <dfn id=htmlparamelement>HTMLParamElement</dfn> : <a href=#htmlelement>HTMLElement</a> {
@@ -21862,7 +21862,7 @@
    <dd>Empty.</dd>
    <dt>Content attributes:</dt>
    <dd><a href=#global-attributes>Global attributes</a></dd>
-   <dd><code title=attr-source-src><a href=#attr-source-src>src</a></code></dd>
+   <dd><code title=attr-source-src><a href=#attr-source-src>src</a></code> <span>(required)</span></dd>
    <dd><code title=attr-source-type><a href=#attr-source-type>type</a></code></dd>
    <dd><code title=attr-source-media><a href=#attr-source-media>media</a></code></dd>
    <dt>DOM interface:</dt>
@@ -27571,7 +27571,7 @@
    <dd><a href=#transparent>Transparent</a>.</dd>
    <dt>Content attributes:</dt>
    <dd><a href=#global-attributes>Global attributes</a></dd>
-   <dd><code title=attr-map-name><a href=#attr-map-name>name</a></code></dd>
+   <dd><code title=attr-map-name><a href=#attr-map-name>name</a></code> <span>(required)</span></dd>
    <dt>DOM interface:</dt>
    <dd>
 <pre class=idl>interface <dfn id=htmlmapelement>HTMLMapElement</dfn> : <a href=#htmlelement>HTMLElement</a> {