
Google introduced a new robots tag indexifembedded to have more control over indexing when a page is embedded with an iframe on another page.
Even if a noindex tag is given to a page, it can be indexed within that page when it is placed on another page with an iframe tag with the indexifembedded tag.
If you don’t want the page indexed, but you do want it indexed by third parties, you can use the new robots tag.
Using the new tag:
<meta name="googlebot" content="noindex" />
<meta name="googlebot" content="indexifembedded" />
<!-- OR -->
<meta name="googlebot" content="noindex,indexifembedded" />Alternatively, you can specify the tag in the HTTP header
X-Robots-Tag: googlebot:noindex
X-Robots-Tag: googlebot:indexifembedded
...
OR
…
X-Robots-Tag: googlebot:noindex,indexifembedded