Categories run from heads of state and senior politicians to senior judiciary, military officers, and executives of state-owned enterprises, with family members and known close associates included by extension.
PEP status is not an accusation and does not require refusal of service. It triggers enhanced-due-diligence, source of wealth evidence, senior approval to open or continue the relationship, and closer ongoing monitoring.
Screening is done against commercial databases at onboarding and periodically thereafter, which is why a change in a customer's employment or a relative's appointment can prompt fresh questions years into a relationship.
Related: enhanced-due-diligence, customer-due-diligence, sanctions-screening, source-of-funds, anti-money-laundering