The restrictions follow complaints from some in the media, namely News Corporation chief executive Rupert Murdoch, that firms such as Google are generating advertising revenues by linking to paid-for news content produced by newspaper publishers.
It is possible to access paid-for content using the search engine.
Josh Cohen, senior business product manager, says that previously each click from a user “would be treated as free”, but the update restricts access to “no more than five pages per day without registering or subscribing”.
“We think this approach still protects the typical user from cloaking, while allowing publishers to focus on potential subscribers who are accessing a lot of their content on a regular basis,” he says.
He adds that Google users could see a registration page after they have clicked through to more than five articles on a publishers’ website in a day.