How we verify
Every contact in every list passes a four-stage verification pipeline before it reaches your dashboard.
Data sourcing
Contact data is aggregated from publicly available professional sources — company websites, professional directories, press releases, and other publicly indexed business information. We do not name our sources. Supply-chain secrecy is part of how we maintain the quality and freshness edge.
Multi-step format and domain validation
Every address passes a sequence of automated checks: syntactic format validation, active domain verification, and MX record lookup. Addresses that fail any step are dropped before the next stage. This eliminates obvious junk before the more expensive checks run.
Live deliverability checks
This is the step most vendors skip or charge extra for. We verify each address against the receiving mail server — including addresses behind catch-all configurations that standard verifiers cannot confirm. When a Quarvio contact is marked valid, it has passed a live send-path test. Not a format check. Not a domain ping. A real deliverability confirmation.
Human quality review
Before delivery, each fulfilled list goes through a final manual review pass. We check for data coherence against the order filters, flag outliers, and confirm the contact-to-filter match rate is within acceptable range. Lists that fail the review are re-run rather than delivered short.
Catch-all addresses — verified, not discarded
Catch-all addresses cover a large share of corporate decision-makers. Most vendors delete them or flag them “risky” and dump the bounce risk on you. Our live deliverability checks confirm catch-alls at the server level. When a Quarvio contact says valid, it's valid — no asterisks, no hedging.
90%+ deliverability guarantee
Every list ships verified. If deliverability falls below 90% on a delivered order, report it within 7 days of delivery and we return credits for the difference — no questions, no forms, no waiting for a policy review.
How to claim: email hello@quarvio.io with your order ID and the bounce export from your sending tool.