Allegrow

Workvivo’s sender reputation went from 60% to 96%. Same outbound workflow. Different verifier. Sender reputation collapses when your tools can’t tell the difference between a real contact and a catch-all server. Every bounce, every spam complaint, every dead inbox compounds, and ISPs start filtering your domain. Allegrow rebuilds the foundation: definitive Valid / Invalid on catch-alls, primary mailbox detection, automated greylisting resolution for Proofpoint and Mimecast. Your reps send to real people. Your domain reputation recovers.

4x fewer bounces. Across the same 10,000 contact list. Same workflow, different verifier. Most verification APIs hit catch-all servers and return “Unknown”. Your customers discard those contacts as risky. The valid ones get thrown out with the invalid ones. Allegrow returns conclusive Valid / Invalid on the catch-alls legacy APIs give up on. 100M+ requests. Custom pricing for data providers.

100M+ verification requests. 0.8% bounce rate on enterprise lists. That’s what your API needs to handle, and what legacy SMTP-only tools weren’t built for. Allegrow’s triple-verification method (Syntax + SMTP + proprietary signals) was built for the contacts that actually matter to B2B: catch-all servers, Secure Email Gateways, corporate mailboxes. Custom pricing at scale. SOC 2-certified. Enterprise DPAs.

Quantum Metric. Algolia. Apollo. Decagon. RightBound. Data providers and high-velocity GTM teams replaced their legacy verification API with Allegrow, and unlocked the 30% of contacts their old tool was flagging “Unknown”. No more rationing credits. No more discarding catch-alls. No more false positives burning your customers’ domains.

Verifying millions of B2B emails? “Unknown” shouldn’t be the default outcome. Legacy APIs struggle on enterprise and catch-all servers, when secure email gateways and greylisting block simplistic SMTP checks. Get API access and put Allegrow to the test using our triple-verification method (Syntax + MX/SMTP + proprietary signals) and customizable verification logic. SOC 2-certified, with enterprise DPAs for data providers.

Your customers cancel when your email contacts bounce. Every “Unknown” returned is a lead they lose. Every spam trap missed is a domain they burn. Most verification APIs fail on modern B2B infrastructure, they mark 30% of business emails as “Unknown” and miss the threats that damage customer reputation. Allegrow replaces legacy verification with signals-based precision: ✅ Conclusive Valid / Invalid on catch-alls ✅ Identifies spam traps & non-primary mailboxes ✅ Verifies behind Proofpoint & Mimecast SEGs ✅ Stops false positives that burn customer domains ✅ Scales to 100M+ requests ✅ Quality IPs fully managed Don’t let a legacy API drag down your retention metrics.