As noted elsewhere, Elsevier has recently announced that:
Initial experimental results submitted to Physics Letters B and Nuclear Physics B by the LHC experiments will be made available through Elsevier’s sponsored access option at no cost to the experiments.
About one year ago Springer made a similar statement, extended to all HEP experimental papers, announcing
...all experimental papers submitted to and accepted by The European Physical Journal C - Particles and Fields will be published with full, online open access without any fees being incurred by the authors.
These moves by Elsevier and Springer mean that the peer-reviewed papers will not only be available for any and all parties to read, but that neither the authors nor their institutions will need to pay for this Open Access.
Of course, these sorts of donations to the HEP community (Elsevier and Springer incur very real costs to review, edit, and publish these papers, which they are here donating to the community) can be seen as a marketing ploy, designed to attract the goodwill of the HEP community and, with it, several of what one surely expects to be notable, highly-cited articles in the field.
However, the interesting bit is not that Elsevier and Springer might attempt to obtain high-quality articles for their journal, after all, that is their responsibility to their shareholders. Indeed the interesting thing here is that they feel that providing Open Access for LHC papers will actually attract LHC papers. Remember that authors in HEP pay essentially no fees in any of the primary journals in which they publish, so they do not really have a direct incentive to publish Open Access. Why then would a publisher (and indeed clearly smart ones like Elsevier and Springer) feel that providing Open Access for free would be a selling point?
Indeed this is the real story behind this action: that Elsevier are responding to new forces in the market for scholarly publishing. The rise of Open Access movements in general, and SCOAP3 within HEP, are a sign that the scientific community is starting to ask for more control over the dissemination of their work. Researchers are increasingly asking for journals that fit their mode of discourse, rather than journals that are bound to traditional ways that might not fit their optimal working style.
In addition the LHC experiments have made clear statements that they will publish their articles under Open Access conditions, and, as reported in symmetry, chose to publish key papers about the construction of their experiments as Open Access in JINST. These publishers appear to think that Open Access is something researchers want, and that providing it will get them a leg up in the marketplace.
The real story is that researchers, librarians, and other Open Access advocates have changed the rules of the game, so that not only does the world's largest scientific publisher feel that giving away articles free is good business, but they are probably right.