Andrew Katz, partner at the law firm Moorcrofts LLP, has published the results of a survey into free and open source silicon (FOSSi) licensing concentrating on processor cores – which includes AB Open’s Andrew Back among its interviewees.

Andrew Katz’ report was commissioned by Western Digital, which recently released its own RISC-V based SweRV Core under a permissive licence, in early 2018; the version published this month in the journal International Free and Open Source Software Law Review represents an edited version for public use. As well as AB Open’s Andrew Back, industry experts interviewed for the report include Krste Asanovic, Julius Baxter, Dr. Jeremy Bennett, Alex Bradbury, David May, Simon Phipps, and Dr. Davide Rossi.

“All interviewees believed that the most commercially effective open hardware core designs were those which adopted permissive licences,” Andrew’s report explains. “The prevalence of these licences is borne out by desktop research. The stated various reasons for this are: that the currently available copyleft open hardware licences are insufficiently clear in their effect to be safely used; that the potential benefits of copyleft licensing in core designs are not yet sufficiently clear to show an overwhelming need to shift to a copyleft model; that copyleft licensing is certainly interesting and may have a place as the market matures. No interviewee was against copyleft core licensing in principle (although there was consensus that a weak copyleft with clearly defined boundaries was more likely to be commercially successful).”

One particularly interesting aspect of the report is the universal popularity of the open RISC-V instruction set architecture (ISA). “Note that even though the interviewees selected were intended to represent a cross section of the core-developing communities, RISC-V was referred to by every interviewee. The emphasis on permissive licensing may therefore be an artefact of the relatively small sample size and a shared familiarity by the interviewees with RISC-V. It may, on the other hand, reflect a reality that RISC-V is the most prominent and widely adopted open ISA currently in use.”

The full report is available to read now in International Free and Open Source Software Law Review Volume 10.