SiFive, a US-based fabless provider of customised semiconductors based on research at University of California, Berkeley, revealed Intel Capital, the corporate venturing arm of chipmaker Intel, participated in its $50.6m series C round.

The round, closed a month ago, was co-led by spinout-focused investment firm Osage University Partners, Sutter Hill Ventures and Spark Capital. It also featured SK Telecom, part of conglomerate SK Group, wearable device producer Huami and computer storage vendor Western Digital.

Founded in 2015, SiFive produces customised semiconductors using instruction set architecture (ISA) Risc-V (pronounced “risk-five”), the part of a computer that tells the processor what to do.

Risc-V ISA is free and open to use, with SiFive generating revenue by customising chips for a client’s needs through a service called Freedom Platform. Western Digital has signed a multi-year licence for the platform to produce a billion Risc-V-based cores.

Risc-V is based on research by then-PhD candidates Yunsup Lee and Andrew Waterman with Krste Asanovic, professor in University of California, Berkeley’s Department of Electrical Engineering and Computer Sciences.

The series C round is being used to commercialise additional products based on Risc-V. The company has raised $64.1m in funding to date.

Osage University Partners backed an $8.5m series B round in May 2017 led by Spark Capital, with participation from Sutter Hill, the latter of which was named a returning investor though details about its earlier commitments have not been disclosed.