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Open standard but not open access: Schematron author complains about ISO paywall

'This is shooting Schematron in the heart ... its heart is individual open source developers'

The original inventor of a popular XML standard, Rick Jelliffe, who created Schematron, has protested that the widely used text is now behind a paywall at standards body ISO.

Schematron is a language for validating XML, designed for processing XML documents and reporting on errors. Version 1.0 was developed in 1999, since when it has been enhanced and standardised, with the latest version being ISO/IEC 19757-3:2020.

This replaced the 2016 version: ISO/IEC 19757-3:2016.

The Schematron standard is one of those administered by a JTC (Joint Technical Committee), called ISO/IEC JTC 1/SC 34, which oversees "Document description and processing languages."

In the case of the 2020 edition, which is some corrections and additional annexes only to the freely available 2016 edition, it is ridiculous bastardry on ISO's part

This also includes both the Microsoft-sponsored Office Open XML and the OpenDocument format used by LibreOffice and Apache OpenOffice, in liaison with other standards groups including Ecma International and OASIS.

To clarify, it is the text of the standard – which is copyright ISO/IEC - that is at the heart of the issue. The technology itself cannot be copyright (and has no IP).

Last month Jelliffe, who is no longer directly involved in editing the standard, posted to "note with extreme displeasure that ISO/IEC has recently reneged on its policy of making available free PDFs for standards that were brought into ISO from the outside: they want you to buy it.

"In the case of the 2020 edition, which is some corrections and additional annexes only to the freely available 2016 edition, it is ridiculous bastardry on ISO's part."

Jelliffe said that "the core library technologies are almost entirely implemented or maintained by private individuals as open source projects (such as David Maus' SchXslt): these small or not-for-profit developers should not have to abruptly fork out $175 for the 2020 edition, which differs only in a few pages from the freely available 2016 edition."

The 2016 version, he said, is still available for free; though when we tried to follow the link he gave we got "the page you're looking for has either moved or no longer exist," from the ISO Standards Maintenance Portal. The latest version however is on offer here for CHF158, or around £125.

Buy this standard: displeasing to its open source authors

Buy this standard: displeasing to its open source authors

'The assumption I came in on was that the standard would be available to the public'

We asked Jelliffe to expand on his claim that ISO reneged on its promise. "I invented Schematron in 1999, and it quickly became popular, in its tiny niche, and has remained so. There was demand for it to become an industrial standard, along with RELAX NG, so SC34 invited me to be the editor of the first edition of the Schematron standard.

"As with RELAX NG, because this was an an open source project from the beginning, the assumption I came in on was that the standard would be available to the public, and indeed ISO made the PDFs available for free individual downloads, which was plenty good enough. The most recent revision to the standard merely adds a few pages and makes some minor corrections, it does not change the basic technology or text. As no major or breaking changes have been made, it is not reasonable to stick a new version number and deem it to be suddenly a new thing that different rules should apply to," he said.

"I have no problem with ISO deciding to restrict how new future standards are made available: my problem is that Schematron has been widely adopted in its niches because it has had the ISO international consultation and QA process on the documentation (which is what standardization is all about), such as it is, and because individuals could read the standard freely.

"Changing the availability of an existing standard like this is shooting themselves in the foot, and shooting Schematron in the heart:its heart is individual open source developers," he added.

Jelliffe designed Schematron to be useful not only to corporations but also to individual developers. "One of the original design considerations was keeping Schematron small enough that an individual developer could easily implement it," he said.

The Register asked ISO to comment, and were told it was a matter for the committee to decide. "This standard is an ISO/IEC standard and it is unfair to say that ISO and IEC, since this is a joint management and decision, has reneged of the freely available status. We are not reneging the freely available status). It’s simply not requested by the committee," a spokesperson told us.

"The topic of the freely standard has been discussed within the joint ISO/IEC technical committee, JTC 1/SC 34, Document description and processing languages, and the standard no longer meets the criteria for free availability. The main reason for coming to this conclusion is that there is no longer a technically equivalent specification in the public domain, as it was the case originally," they continued.

Freely availability of a standard is not granted for life, the spokesperson said, but "is a process that requires validation for each edition."

We have tried to contact the committee and will report back any further comments.

The issue in general is not a new one. "Could somebody link me to the official ISO-8601 date format reference? (not to Wikipedia or PDFs behind a paywall)?" asked F-Secure researcher Mikko Hyppönen on Twitter adding that "apparently, the best way to make sure everybody follows international standards (such as the ISO standards) is to make sure the specifications are not available for free download."

Security researcher Mikko Hyppönen complains about paywalled standards

Security researcher Mikko Hyppönen complains about paywalled standards

"Unfortunately, the ISO Central Secretariat does not provide free copies of standards. All ISO Publications derive from the work and contributions of ISO and ISO Members that contain intellectual property of demonstrable economic value," was the reply from the official ISO Twitter account – which did not go down well with open source advocate Simon Phipps, who remarked that "this suggests ISO standards should not be cited normatively by national laws of any country."®

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