Google means, it does its best to correctly recognize the content in
iframes are indeed violation against w3c, because
iframes establish situation, where one url could get more then one head (one head of the site, and other head of the
iframe src site).
My strong recommendation, if you make use of
iframe, do explicit control of the
- if you want
iframe content is indexed, don't use
<head></head> on the
iframe src page - just put the content in it.
- if you don't want
iframe content is indexed - use
<head><meta name="robots" content="noindex" /></head> on the
iframe src page. To close
iframe src pages with
robots.txt doesn't help, because
iframe src pages are linked.