Stop worrying about IP blocks, proxies, and greylisting. Allegrow’s infrastructure solves the most complex backend of verification (including catch-alls and SEGs) so you can verify millions of contacts and accelerate reliable data acquisition.
10K data sample. Enterprise-grade accuracy. SOC 2 compliant.
Simple SMTP checks fail against Catch-alls and Secure Email Gateways (SEGs). Legacy tools then often mark valid enterprise contacts as "Catch-all" or “Unknown” because they cannot verify contacts on complex email servers. You are unknowingly discarding high-value inventory and losing net-new data coverage.
Legacy vendors struggle with temperamental EHLO & RCPT TO requests. When their IPs get blocked or greylisted, you get "Unknowns" or false invalids. Your data quality suffers simply because their infrastructure lacks the dynamic proxy management and automated greylisting resolution needed to maintain access.
Old-school verification methods and syntax-guessing often return inactive alias emails and incorrect catch-alls as valid. Without Primary Email Detection, you blindly deliver messages to these inactive accounts that have 0% chance of generating engagement, directly hurting your customer retention.
Stop worrying about ESP changes and verification variance. Allegrow acts as the SOC 2 compliant infrastructure layer that improves your data quality and acquisition without any scraping or sending.
Run millions of requests daily without hitting infrastructure walls. We maintain enterprise-grade quality at scale using years of R&D on custom throttling, proxies, and IP selection to reliably verify email contacts on even the most challenging catch-all servers and gateways. This proprietary logic surfaces incorrect emails and flags job changes faster than SERP-reliant data.
Stop discarding revenue due to false negatives. Our system automatically resolves greylisting, avoids IP blocks, and verifies emails on Catch-all servers to resolve "Accept-all" and "Unknown" statuses. This stability allows you to safely verify multiple email permutations for any contact — establishing net-new addresses before they are public, so you are the first builder to validate a new hire.
Gain granular control over how your dataset is processed and organized. Choose between synchronous (real-time) or asynchronous (bulk) verification pipelines to match your product's data workflow. Then, customize the verification logic itself: define your preferred mix of standard SMTP checks versus alternative signals-based methods. Our detailed status insights provide total transparency into the reason for every valid or invalid result. You can distinguish between standard SMTP results and our advanced signals, giving you insight into how to treat each contact in your dataset.
Legacy APIs are blind to the reality behind catch-all servers, leading to "Unknown" gaps or dangerous false positives. In this technical breakdown, see how Allegrow definitively resolves these contacts, ensuring you only deliver accurate, validated data.
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Run a free side-by-side test on your hardest data.
"We’ve tested multiple email verification providers, and Allegrow has provided unique accuracy and being able to verify catch-all & B2B enterprise emails." As a platform that automates outbound prospecting for sales teams, RightBound aggregates data from dozens of sources. They leverage Allegrow to ensure that the millions of B2B enterprise contacts they process meet the highest deliverability standards before reaching their clients.
"One problem we saw Allegrow could solve [...] was creating quality assurance around how fresh our email contact data is. For Example, there’s data that could have come into our CRM and been fresh at the time, but if reps are re-prospecting old accounts [...], this could easily turn into emails that bounce. [...] Allegrow will analyze this data and make sure those bounces are avoided. This was a unique and powerful capability that no one else offered."
"In the first 12 months, using the Safety Net (SN), we prevented 75,000 harmful contacts from entering cadences, which helped safeguard our domain reputation. [...] which led to us almost doubling email send volume while keeping bounce rates below 2%. We’ve also managed to stay on top of our sender reputation score, which has reached 97%"
You can, but simple SMTP checks fail against corporate mailboxes. To identify threats behind B2B servers, you need a signals-based system. Building this logic isn't a one-time sprint; it requires massive datasets and a permanent maintenance tax to keep up with changing server responses and firewall rules. Partnering with Allegrow prevents your team from spending cycles fighting reputation blocks.
Legacy tools rely on server responses alone, which fail on catch-alls. Allegrow supplements this by analyzing proprietary signals to detect the difference between a real active inbox and a silent re-route or a spam trap. This allows us to confidently provide a definitive "Valid" or "Invalid" status where others are forced to return "Unknown".
Legacy tools use syntax guessing and SMTP, which returns multiple "valid" aliases for one person. Allegrow uses new verification methods to flag the primary operational inbox, ensuring you deliver the highest-engagement contact to your customers.
We are built for data providers verifying hundreds of millions of contacts. We offer custom delivery speed, rate limits, and dedicated technical support for high-volume enterprise partners.
Never. Sending fake emails to verify accounts is a dangerous practice that burns IPs and gives unreliable results due to many catch-all emails not providing NDRs. A test email approach would falsely mark these as "Valid," filling your database with bad data. We use proprietary signals to definitively confirm existence, ensuring you don't build your product on false assumptions.
Yes. This is our core differentiator. Our infrastructure is specifically designed to verify contacts behind strict Secure Email Gateways (SEGs) like Proofpoint/Mimecast that block standard verification methods.
We advise against simple side-by-side comparison on unknown data. Instead, we recommend building a controlled sample of ~1,000+ contacts comprising "Known Valids" (recent threads) and "Known Invalids" (synthetically generated permutations). This isolates the variable of catch-all server behavior, exposing exactly how the API handles false positives and re-routes. We have open-sourced the prompts and logic for this test here: Testing Catch-All Email Verification.
You will receive immediate platform access to benchmark your current lists and validate our accuracy firsthand. Simultaneously, a deliverability specialist will reach out to schedule a technical deep-dive with our engineering team, ensuring all your API and infrastructure questions are answered by a technical peer.
Your current API is hiding valid leads and missing threats with false positives. Let's prove it. Request your API consultation and get access to our platform to run a side-by-side comparison on your hardest data.