It isn't quite free, but the IP is available to designers to integrate into their own System-on-Chip (SoC) designs pre-commercialisation, along with supporting peripherals. There's then a fast track process to license the IP when the chip goes into production.
The designs will allow prototyping the the CPU and peripherals on a field programmable gate array (FPGA) before committing to actual silicon.
ARM is also supplying access to the ARM Keil MDK (software developer kits) for 90 days so developers can test their designs.
Once a commercial license has been obtained, ARM will provide use of the ARM Cortex-M0 processor IP, SDK, and Keil MDK development tools, along with ARM technical support.
This should allow start-ups who wish to develop specific SoC solutions to utilise the ARM M0 in their designs without having to pay traditional (large) licensing fees upfront.