Case Study

ContentStudio

Cold outreach to small UK service businesses.
Method: API integration. Leads tested: 85

“Pattern discovery and verification in a single call, and failed searches cost you nothing.”

“Pattern discovery and verification in a single call, and failed searches cost you nothing. It also looks past whether a domain simply accepts mail and checks if the actual mailbox exists.”

Hareem Malik

ContentStudio

Background

The Setup

Hareem built a signal-based cold outreach system targeting small UK service businesses — roofing companies, garage door installers, pest control. His approach: only contact businesses with a recent, public complaint about the exact problem he was pitching.

Out of thousands scanned, only ~5% made the cut. Then he filtered again by recency — only complaints from the last month. The final list: 85 high-intent leads.

For email finding and verification, he ran a waterfall with filtrat as one of two providers.

Results

The Real Found Rate

The headline number was 58% — but that blends two different things.

Breaking down the 85 leads

Personal email found: 49 (58%)

Generic inbox only: 15 (18%)

No email exists: 21 (25%)

0/49

Personal emails found

Personal emails missed

Every single personal email that existed was found.

Accuracy

Found Rate by Email Type

What also worked

Pattern discovery and verification in a single API call
No charge for failed searches
Catch-all detection caught a wrongly-deliverable address

The gap

The 15 “misses” were all generic company inboxes — info@, enquiries@, contact@. Not a single first.last@ or first@ was missed by the finder.

Transparency

The Honest Gaps

The finder’s 58% rate includes a manual fallback process Hareem built. The finder alone found fewer — primarily because it doesn’t try role-based addresses (info@, enquiries@, contact@) as a last resort.

For SMB outreach where generic inboxes are often the only working email, this is a real gap.

What we’re working on based on this feedback:

WIPRole-based address fallback for SMB domains

Hard time limits for slow mail servers (14 searches took 30+ seconds)

Smarter early exit so the finder doesn't waste 60s on a dead end

Summary

Key Numbers

Leads tested	85
Found rate (with fallback)	58%
Cost for failed searches	$0
Catch-all correctly identified	Yes
Role-based emails missed	15
Personal emails missed	0
Time to ship fixes	Same week

Bottom Line

Takeaway

Filtrat’s finder works well for companies with standard email patterns. For SMB outreach targeting small businesses with generic inboxes, the found rate was lower than expected — but every miss was a role-based address, not a personal email. The fix is shipping now.

“Failed searches cost you nothing” means the economic risk of a lower found rate is absorbed by filtrat, not the user.

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