The latest specifications are now only available to people who agree to become a member of the Infiniband organisation.
But even if you pay $9,500 for a copy of the specification on CD-ROM, that is subject to a set of licence terms and conditions with some important restrictions.
For example, that asserts patent and copyright licences are held by the Infiniband Trade Association and precludes people or companies from using the spec for commercial use.
The Infiniband specifications, after a tortured period when Intel faced off large other vendors, is a result of collaboration from a large number of engineers at a large number of companies.
Seven firms - Compaq, Dell, HP, IBM, Intel, Microsoft and Sun said back in August 1999 that they would merge the best ideas of Future IO and Next Generation IO architecture into one spec for server and peripheral vendors throughout the industry.
When it released the first spec, version 1.0, you could download it for $19.95 or buy a CD for $49.95, as this press release shows.
The web site, which you can find here has the tagline "Bandwidth without Barriers".
But the INQ wonders if the move, which appears to have happened quite recently, is a sign that things are not as much rosy as thorny over at the IBTA.
Sign up for INQbot – a weekly roundup of the best from the INQ