OSINT, SOCMINT, cyber threat intelligence, entity resolution, identity intelligence, behavioural analysis, network and link analysis, digital forensics, and dark web intelligence.
Every Greyline engagement draws on a defined set of intelligence disciplines, combined according to what the specific question requires:
Which disciplines apply to a given engagement is set out in the written scope, not assumed — a personal relationship verification draws on a different combination than a corporate insider-threat investigation, and the scope says which.