HTTP Referrer Gotchas?

Question

I need to ensure that my webpage is always within an iframe owned by a 3rd party. This third party refers to our landing page using src="../index.php".

Now my question is, if I make use of referrer to ensure that the page was requested by either myself or from the third party and if not force a reload of the 3rd party site, are there any big gotchas I should be aware of?

For example, are there certain common browsers that don't follow the referrer rules?

Thank you.

Answer 1

Also, it's REFERER because it somehow got misspelled in the spec. That was my very first REFERER gotcha.