Answer
PECCS™ is the acronym for PrivatE Company Classification Standard, the taxonomy of private companies, developed and maintained by EDHEC Infrastructure and Private Assets Research Institute, that covers a broad range of risk factors that cannot be captured by considering the industrial activity of a company alone.
The pillars of PECCS include:
Industrial Activity
Lifecycle Phase
Revenue Model
Customer Model
Value Chain.
Each of these pillars has clearly defined, mutually exclusive, and comprehensive classes, into which private companies can be easily assigned, following the methodology available here.