Authorized data
Use lists you own or are lawfully authorized to process.
Responsible verification
Respect provider policies, rate limits, and inconclusive evidence.
Permission-based operations
Verification does not create consent to send email.
Prohibited activity
- Credential attacks, password testing, phishing, fraud, harassment, or unlawful account discovery.
- Spam operations, purchased or unlawfully obtained lists, scraped personal data without lawful authority, or deceptive messaging.
- Bypassing access controls, rate limits, suspensions, provider blocks, or infrastructure protections.
- Disguising verification traffic, rotating infrastructure to evade policy enforcement, or misrepresenting sender identity.
- Violating law, privacy rights, contractual restrictions, or third-party rights.
SMTP and catch-all safeguards
Network verification is non-sending: it does not authenticate or transmit message content. It must remain conservatively rate-limited. Policy or reputation blocks are treated as unknown—not as evidence that a mailbox is invalid. Catch-all results describe domain behavior and do not prove an individual mailbox exists.
Enforcement
We may investigate, rate-limit, suspend, or terminate activity that threatens customers, providers, infrastructure, or legal compliance. Contact support@bestsender.app if you believe enforcement was mistaken.