The Library of Trinity College Dublin in Ireland. Credit: David Iliff, CC BY-SA 4.0

On 30 May, many pay-to-read academic publishers breathed a sigh of relief. That day the funding agencies spearheading Plan S decided to delay the implementation of the bold open-access (OA) initiative by a year, to 2021, and announced some changes in response to scrutiny from publishers, researchers, librarians, and other stakeholders. The modifications include more flexibility regarding where researchers can publish, and a vow from the funders to move away from evaluating academics based on the prestige of the journals in which their work appears.

Even with the changes, there is a “huge amount of uncertainty” around how things will pan out, says Paul Hardaker, CEO of the UK’s Institute of Physics (IOP). Outstanding issues include the role of hybrid OA journals and the impact on researchers outside Europe, who may have to pay heftier fees to publish in journals that have switched models to comply with Plan S.

Originally unveiled late last year by a group of European funding agencies known as Coalition S, Plan S will require researchers who receive money from the coalition to publish in journals whose contents are free to read immediately. Either the coalition members or researchers’ host institutions will cover the OA publishing fees for the work they support. Plan S has the backing of the European Commission and the European Research Council, so all scientists supported by the European Union’s next major research funding program, the €100 billion ($114 billion) Horizon Europe, will have to comply.

Since its rollout, Plan S has drawn criticism from several publishers, particularly those that charge researchers or their institutions a subscription fee for journal access. Some have said they agree on the wider aims of the project but take issue with the details, such as the plan’s rejection of the hybrid OA journal model, which is subscription-based but allows authors to make their papers freely available by paying a fee.

In February the European Physical Society (EPS) issued a joint statement with the European Association for Chemical and Molecular Sciences warning that rushing enforcement of Plan S could cause “irrecoverable damage” to academic publishing in Europe, especially among not-for-profit publishers. IOP previously expressed similar concerns and suggested changes that include allowing researchers to publish in hybrid OA journals and extending the implementation period.

Coalition S—which currently includes the Italian National Institute for Nuclear Physics, the UK’s Wellcome Trust, and the US’s Bill and Melinda Gates Foundation—accepted some of those suggestions in its recently revised plan. The agencies pushed the implementation date of Plan S forward to 1 January 2021, giving publishers an extra year to make sure their journals comply. And researchers will be allowed to publish in at least some hybrid OA journals; through 2024, Coalition S agencies will cover the cost of authors publishing in hybrid OA journals that are deemed “transformative”—working toward fully open access.

The funders also announced that they no longer plan to set caps on the fees OA journals can charge for publishing articles. Critics had argued that making the caps too low might incentivize publishing many low-quality papers rather than fewer high-quality ones and would favor large commercial publishers, which have the resources to publish more papers than do smaller learned societies.

The revised plan includes a pledge that Coalition S agencies will ignore the prestige of the journals that researchers publish in when making funding decisions. That has been a major concern for researchers because under Plan S, they would be barred from publishing in high-impact journals like Nature and Science (unless the publications made changes at their end). “Committees still look at the impact factor of journals when judging researchers, and the top journals are not open access,” says Frank Miedema, an immunologist at Utrecht University and an ambassador of Plan S in the Netherlands.

Paul Ginsparg, a physicist at Cornell University who founded the arXiv preprint server, says he is skeptical that funding agency reviewers will be able to simply disregard where applicants have published in the past. “If you have the information, then how do you know it’s not having some conscious or subconscious effect?” he says.

Stakeholders are also worried about the issues Coalition S didn’t address in its latest announcement. “We are concerned about Plan S because it doesn’t always take into account the very international nature of scientific publishing,” says EPS secretary general David Lee. For instance, researchers and institutions based outside Europe may not be able to afford the publishing fees for compliant journals. “It’s always difficult when a policy initiative is a one-size-fits-all,” Lee says.

Not everyone is dreading the approach of Plan S. Toma Susi, a materials physicist at the University of Vienna and vice chair of the Young Academy of Europe, a pan-European network of junior academics, notes that many physicists already post their papers on arXiv. The easiest way for journals with physics content to become compliant with Plan S, he says, is to make sure their preprint policy allows researchers to post final-version or accepted manuscripts on arXiv. Currently, many journals have restrictive copyright policies that prohibit such versions from being posted online.

“I don’t really think we need to necessarily do things very differently or that there will be significant negative impacts of Plan S for researchers,” Susi says. “The whole point is to change the system. If you keep criticizing the plan solely on the basis of the status quo, you’re missing the point.”