Case Study: 5th Line achieves 4.5x more replies with Amplemarket

How 5th Line scaled high-touch sales with Duo Copilot to record 4.5x more replies & 10x signal engagement

5th Line is a Boston-based financial services advisory firm helping growth-stage companies with venture debt and CFO services. The team relied heavily on referrals and had a fragmented, manual outbound process across multiple tools, with no real-time intent data to time outreach effectively. They also struggled with email deliverability, which limited their ability to scale cold outbound.

With Amplemarket’s all-in-one AI sales platform, including Duo Copilot, intent signals, job change alerts, social prospecting, and built-in deliverability tools, 5th Line unified its sales stack and made outreach more strategic and personalized. Amplemarket helped them achieve 4.5x more replies from AI-recommended leads, 10x more replies from top AI-recommended signals, 2.1x more opens, and a bounce rate below 2.5%, while expanding from 4 to 15 mailboxes to scale outreach sustainably.

5th Line

Chandler Minaldi

Head of Growth