The IAB SafeFrame specification has been released in March 2013 and aims to replace old forms of iFrames used for ad tagging. The specification is related to 3MS initiative.
Goals of SafeFrame specification are:
to improve measurement of ad viewability
to better separate ad and web page
to better protect web page data
to better protect consumer
to ease campaign deployment by larger specification adoption
to improve rich media usage and rendering
to ease cross-platform campaign
SafeFrame specification is also based on iFrame and offer an API that allows, with publisher control, external content to communicate with page content.
SafeFrame doesn’t directly measure viewability but offer the capacity to measure in-view metrics such as duration and in-view percentage which, can be used for viewability reporting.