Press Release Sites See Huge Drop In Google Ranking After Panda 4.0

Yesterday I reported at Search Engine Land thatPanda 4.0 may have hurt press release sites and showed SearchMetrics data for PRWeb, PR Newswire, BusinessWire and PRLog all losing between 60% to 85% of their SEO visibility.

This drop seems to have come right after the Google Panda 4.0 update. The controversy around press release sites were mostly about links flowing from those releases, not necessarily the issue with the duplicative nature of that content. But let's be honest, many many press releases issued are content thin and spammy on the content end, not just on the link end. So maybe, just maybe, Panda 4.0 adjusted for it and the big sites felt it?

Sean from SEER also documented the drop via SEM Rush data and screen shots of before and after rankings for some press releases.

Here are SearchMetrics charts:

Was this a Panda thing? It is not clear. It seems like it but these be manual actions also, similar to the overlap with eBay?

Forum discussion at Google+ and Cre8asite Forums.