Are "Redirect 303 & Iframe" types of backlinks?

[zant]

Are "Redirect 303 & Iframe" types of backlinks? google count them?

[RyanPurkey]

Mostly no on iFrames, or not in a reliable way. Redirect 303 is more uncommon, but similar to a 302. Either one is not the way to permanently send old content to new. Google has a guide on redirection here: https://support.google.com/webmasters/answer/93633, and iFrames here: https://support.google.com/webmasters/answer/34445.  Cheers!