Yahoo now supports a way to flag that part of your page shouldn't be included in the search engine index. It's called the robots-nocontent tag.

With new robots-nocontent tag you can tell Yahoo to not index part of your page. Simply use the tag to surround text you do NOT want included in Yahoo’s index.

For this you need to have a class attribute called robots-nocontent assigned to some tag within your document. The attribute looks like this:

class="robots-nocontent"

Now let's say you have a paragraph of text you do not want indexed. You could use the <p> paragraph tags with this class attribute to flag the content as not to be indexed.

This is how robots-nocontent would be added:

<p class="robots-nocontent">
This text won’t be indexed by Yahoo!
</p>

You can also use robots-nocontent in container tags like <SPAN> or <DIV>. For example,

<div class="robots-nocontent">
<p>
This text won’t be indexed by Yahoo!
</p>
<p>
This text won’t be indexed by Yahoo!
</p>
</div>