The publisher of the prestigious Nature family of scientific journals today unveiled a new approach to freely sharing papers that are normally protected by a paywall. The initiative seeks to provide an alternative to—and potentially end—so-called dark sharing, a practice that some scientific publishers find problematic.

It’s an open secret that scientists routinely share papers from journals that require a subscription with people who haven’t paid up. It’s easy: A subscriber just downloads a PDF copy and e-mails it out, or drops it into a shared Internet folder.

The problem is that all that activity is “happening in the dark,” says Grace Baynes, head of communications for Nature Publishing Group (NPG), which produces Nature and 48 sister subscription journals. That means publishers can’t accurately gauge browsing statistics and tell customers (such as university libraries) or authors how often specific papers or journals are being read. And for the public at large, most of whom learn of scientific advances from news media, the original papers remain inaccessible. (At least for 6 to 12 months after publication; many journals make papers older than that freely available).

NPG wants to make sharing easier. The pilot initiative, which will last 1 year, has two elements. In one, NPG subscribers will gain the option of sharing a link to a read-only version of any paper with anyone, via e-mail or social media. The link encodes the identity of the subscriber who’s doing the sharing and the paper being shared. The link will lead to a full version of the paper within ReadCube, a content management system created by Digital Science, another division of NPG’s parent company, Macmillan Publishers. The ReadCube version of the paper cannot be downloaded or printed by nonsubscribers. But the system will allow the sharer to annotate the paper, and anyone who registers with ReadCube will be able to maintain a library of papers.

In addition, for an initial group of 100 news outlets and science blogs, any link to an NPG paper in a story will reroute to the read-only version of the paper (unless the reader is already logged in as a registered user).

The initiative is the brainchild of Timo Hannay, a former neuroscientist who is now managing director of Digital Science. The goal, he says, is to help scientists avoid “using clumsy, time-consuming practices” and “enable collaboration.” NPG will be “looking out for misuse” during the trial period, he says. For example, he says automatically posting links to all current Nature papers, or posting screen-grab images of the papers, will be frowned upon. But misuse is not a huge concern, he adds.

NPG’s free-sharing effort is “an interesting addition to others currently under way” at other subscription journals, says Kent Anderson, the publisher of Science. For example, some journals, including Science, already provide authors with a link to a free copy of their paper that can be placed on a personal or professional Web page (although the link cannot be published anywhere else). Other subscription journals have experimented with systems that allow scientists to share papers with non-subscribers. The American Institute of Physics (AIP), for example, which publishes 17 journals, tested a similar system, called UniPHY, from 2009 to 2012. AIP is now “planning and implementing a major upgrade,” says AIP Director Fred Dylla. A report on collaborative paper sharing is expected within the next few months from an academic publishing industry task force, Anderson says.

NPG’s sharing strategy is being greeted with mixed reactions from advocates for making scientific publishing more open. "It's definitely a step forward,” says Peter Suber, head of the Harvard University Open Access Project. But one concern, he says, is that “because it's so much easier for authors to share links rather than PDFs, it might diminish the amount of self-archiving of papers by authors.” (Self-archiving is posting the paper, or a near-final version of it, on a publicly-accessible web site.) “Nature has not only permitted the archiving of papers in Open Access repositories, they have encouraged it,” Suber says. “I hope they will continue to encourage it.”