The casual non-corporate polity Mensah leads, whose lax security leaves her exposed off-world.
The Preservation Alliance is the non-corporate political entity that Dr. Mensah leads and that offered Murderbot a home. In book four it is off-page but consequential: its members Arada, Overse, Bharadwaj, and Volescu left Port FreeCommerce for home some thirty cycles before the story opens, and Murderbot bitterly notes Preservation's extremely casual attitude toward protecting its leaders—at home Mensah needs no security at all—as exactly the naivety that has left her dangerously alone in hostile corporate space. Preservation has made no official statement about her situation beyond confirming she is on TranRollinHyfa.
A polity, not a person; represented by its people and its notably relaxed, trusting culture.
Mensah's home polity; the trusting culture whose lax security frames the crisis.
Also appears in books you've already read — spoiler-safe to their endings: