Different regimes apply in different places, covering consent, disclosure, record keeping and the right to be removed. Business contact data generally enjoys more latitude than consumer data, but it is not unregulated.

Practical obligations that hold almost everywhere: identify yourself, state why you are calling, keep records of source and consent status, and remove people on request.

Buyers should ask any data vendor where records come from, how often they are refreshed and how removal requests are handled. A vendor that cannot answer is a risk.