For those who came in late, the Intel Management Engine is a separate CPU which is part of the main chip. It is widely hated because it relies on signed and secret Intel code, isn't easily alterable, isn't fully documented, and has been found to be vulnerable to exploitation. It can also run when the computer is switched off. This makes it a potentially hackable computer that you cannot totally control, nor opt out of, but it can totally control your system.
Purism has seen a market for those who don't want Intel's tech controling their corporate notebooks. In a press release it said: "Disabling the Management Engine is no easy task, and it has taken security researchers years to find a way to properly and verifiably disable it. Purism, because it runs coreboot and maintains its own BIOS firmware update process,can release and ship coreboot that disables the Management Engine from running, directly halting the ME CPU without the ability of recovery."
Disabling the Management Engine had been thought to be impossible. Purism is also offering it as a software update for previously shipped recent Librem laptops.
Purism Hardware Enablement Developer Youness Alaou said: "Purism, in the long-term pursuit of liberating hardware at the lowest levels, still has more work to do. Removing the management engine entirely is the next step beyond just disabling it. Coreboot also includes another binary, the Intel FSP, a less worrisome but still important binary to liberate, incorporating a free vBIOS is another step Purism plans to take. The road to a completely free system on current Intel CPUs is not over, but the largest step of disabling the Management Engine is arguably the largest milestone to cross."