Google's John Mueller said in the recent webmaster hangout at the 11:55 mark that those who implement the method of disabling the browser back button will not benefit or be hurt in the Google search results. In short, manipulating the browser back button does not result in a Google penalty.
Why? Because as Google said time and time again, bounce backs don't influence rankings in Google.
John Mueller said the behavior of disabling a user's common navigation is not a good user experience for your web site visitor and it might annoy your visitors. So clearly John doesn't recommend such a practice but for search, it doesn't make a difference.
Here is the video embed:
Here is the transcript question:
I’d love it if someone from Google can chime in about manipulating the browser back button. I see more and more sites doing it and ranking well on pages where they apply this tactic. I know that by looking at this deeper that Google has given a fair amount of weight to page bounce rate and by manipulating the browser back button your are essentially telling Google, no one bounces back to this page.
Here is the transcript answer:
So that is usually something we tend not to have too much problem with from a search point of view. It is definitely not something where you are doing your users a favor by kind of blocking their normal navigation within your web site or across different pages on the web. So that is something where I tend to shy away from looking at that too much or implementing that too much.
But from a search point of view, I don’t think that would cause any problems.
Forum discussion at Twitter.