Fintech reliability, meet dental claims operations.
Mainline sits at the intersection of two worlds rarely built together: dental revenue-cycle operations and financial infrastructure designed for reliable, high-stakes money movement.
Meet the team
Penn Wu
Founder
I began my career in dentistry at Breakaway Practice, where I worked with Scott Leune and Steve Boyd (co-founded ClearChoice Implants), to help bring more than 50 new dental practices to market. During my time there, I worked across practice operations, software systems, and growth equity fundraising.
That experience showed me an early model for helping practices reduce their difficult, operational work by managing call center and insurance operations across hundreds of dental groups and practices.
From there, I spent eight years building software in complex, regulated environments: two years at one of New York’s largest hospital systems and six years in fintech. At Brigit, later acquired by Upbound Group for $460 million, I led an engineering team and built the company’s Credit Builder product. At Cash App and Square, I built core systems behind banking products processing billions of dollars in monthly transaction volume.
Mainline grew out of both chapters. I have dentists in my family, and early in my career I learned how much operational complexity sits behind every successful practice. In fintech, I learned how to build software that makes complex, high-stakes workflows feel consistent, reliable, and scalable.
Mainline brings that same level of reliability and operational control to dental billing teams, starting with the unresolved claims that consume staff time and delay payment.
Claims follow-up is a systems problem. So we're solving it like one.
Mainline turns payer calls into structured claim statuses and clear next actions, so dental groups can work unpaid claims consistently at scale.