The Subscribe to Open model, an open science success story

Science ouverte

The Subscribe to Open (S2O) model is now a success story for mathematics journals that have followed this approach. By setting a threshold for subscriptions that allows journals to function properly, the S2O model guarantees open access to their content, increases the quality of the articles selected and is part of the open science movement. Amandine Véber, Mathieu Lewin and Anne-Laure Dalibard look back on the successes of this transition.

The Subscribe to Open model is a way of asserting that the primary aim of scientific publishing is not to generate high profits, and that access to the publication of an article should not be subject to a level of resources.
Jean-François Coulombel, Scientific delegate for scientific publishing and open science

Profile presentation

Amandine Véber is Director of Research at the MAP51 Field mathematics laboratory and Deputy General Secretary for publishing at the Société de Mathématiques Appliquées et Industrielles (SMAI), EDP Sciences.

Mathieu Lewin is Director of Research at the Centre de recherche en mathématiques de la décision (CEREMADE)2 .

Anne-Laure Dalibard is a professor in the Jacques-Louis Lions (LJLL)3 laboratory and in the Mathematics and Applications Department at ENS Paris. The latter two are chief editors of the journal Annales de l'Institut Henri Poincaré (IHP) C - Analyse non linéaire, published by EMS Press.

  • 1CNRS / Université Paris Cité
  • 2CNRS / Paris Dauphine
  • 3Sorbonne université

The Subscribe to Open (S2O) model

The Subscribe to Open (S2O) model enables open access to journal content, i.e. at no additional cost to either authors or readers. Articles accepted for publication are published as open access under a CC-BY license (rights retained by the authors).

Contrary to popular belief, scientific publication does cost money: the average cost of publishing an article in a journal is estimated at between €500 and €1 0004 , not including the voluntary work of editors/proofreaders, which is difficult to quantify. “Behind each article, there are people who spend several hours laying it out professionally. Ensuring that the published article is connected to all the databases also represents a cost, as does storing and putting these publications online,” explains Mathieu Lewin. The S2O model is triggered when a certain number of libraries subscribe to a journal, as the proceeds from these subscriptions then finance open access for everyone, including individuals or institutions who would not otherwise subscribe.

In order to establish a S2O contract, a minimum subscription threshold is set: to do this, the editorial teams estimate the number of subscriptions required to ensure the journal's viability by analyzing the journal's operating costs in previous years. If the subscription threshold is reached, the articles accepted for publication that year are published under a CC-BY license, enabling them to be consulted on an open-access basis in subsequent years. The challenge is to reach the threshold every year, so that all issues of the journal are in open access without interruption.

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It's a collaborative model, so libraries and institutions need to play the subscription game, and there shouldn't be too many “free-riders” taking advantage of open content without contributing to its funding.
Amandine Véber, Research Director, MAP5 Laboratory

A gradual transition

The Subscribe to Open model has not always been the direction followed by mathematics journals. While the transition to this model is relatively recent, it is a project that has been long considered and sometimes debated within publications. For some years now, SMAI and Édition Diffusion Presse Sciences (EDP Sciences) have been considering ways of opening up the content of their joint publications. Amandine Véber explains: “In 2019, our colleagues at EDP Sciences suggested we try the S2O model, which was little known at the time but which they had identified as promising. It seemed like a very good idea, but on the other hand the lack of information and hindsight on this model made us fear hidden vices, or unexpected difficulties, in its operation. Our exchanges with those involved in French mathematical publishing enabled us to put this model on a solid footing”.

This transition has been well received, notes Anne-Laure Dalibard: “The mathematical community in France is generally in favor of open access models such as Subscribe to Open". But this transition goes hand in hand with a tougher selection of publications, “this can create frustrations, which I understand”, she adds.

A stricter selection of items

The transition to a Subscribe to Open model sometimes presents constraints for journals. In the contract with their new publisher, for example, Annales de l'IHP is required to publish fewer pages in total per year than in the past. “As a result,” explains Anne-Laure Dalibard, “we have to be more selective. “The switch to S2O has raised the standard of the journal,” adds Mathieu Lewin.

Amandine Véber notes that one risk of the S2O model is “the erosion of library budgets, which forces them to make trade-offs that are not always favorable to journals such as those of the SMAI, which have an undeniable international influence but, for some, do not have a sufficiently wide audience to make them a priority when choosing subscriptions”. Certain technical aspects require vigilance. Outside France, for example, some libraries can not purchase a service when it ultimately becomes free, such as access to journal content under an S2O model. “We have sometimes had to adapt, by offering another form of service,” comments Amandine Véber.

An undeniable success, to be disseminated

The Annales de l'Institut Henri Poincaré has taken steps to encourage and disseminate the subscribe-to-open model. For example, the IHP Publications Association is offering subscriptions to certain developing countries, thanks to money left over from the previous publisher. To date, 32 libraries worldwide have benefited from this scheme. In addition, at the end of the year, the team sends an e-mail to authors who published an article in the journal last year, to check whether their library has subscribed. Given that all French libraries are subscribed via the Réseau National des Bibliothèques de Mathématiques ("National Network of Mathematics Libraries" - RNBM), this is particularly useful for checking with contributors outside France. Anne-Laure Dalibard believes that “it gives the community a sense of responsibility: libraries need to subscribe”. Amandine Véber adds that “for some years now, researchers have also been able to support journals using this model through their ANR funding, thus replacing the payment of publication fees with a contribution to the opening of one or more journals”.

For Anne-Laure Dalibard and Mathieu Lewin, working with professional publishers is a guarantee of quality for the publication of articles. “A major advantage of this model is that it is relatively inexpensive to set up for a magazine that already has a certain number of subscribers, since the magazine's mode of financing remains the same (libraries subscribe) but the published content becomes open to all,” adds Amandine Véber.

The S2O model is also another way of responding to the pressure that can be brought to bear by large publishing houses, which often favor the author-pays model. Thanks to the S2O model, libraries and laboratories are able to reconsider their subscriptions if the quality of the journal declines: “this gives publishers an incentive to maintain publications at a very high level. This is not the case with publication fees for authors, since on the contrary, a journal that loses out on excellent submissions may simply accept low-quality articles to compensate for the lost income", explains Amandine Véber.

It's a fairly easy model to set up, requiring transparency in its management and putting the scientific community back at the heart of the decision on which journals to support and which not.
Amandine Véber, MAP5 Laboratory Research Director


Jean-François Coulombel
Délégué scientifique édition scientifique et la science ouverte
Violaine Louvet
Déléguée scientifique données et calcul scientifique
Christophe Delaunay
Directeur adjoint scientifique