Most small businesses have something in common: they are run by reluctant operators. These are owners who set out to provide a service to their local community, and ended up running a business instead. They did not sign up to become finance people, HR people, recruiters, billers, or claims specialists. They became those things because someone had to.
Dental practices are a perfect example. Dentists go to school to practice dentistry and care for patients. Instead many are stuck doing paperwork, hiring people, training and retaining staff, negotiating insurance contracts, fighting claims, and managing cash flow.
Across roughly 160,000 dental practices in the U.S., this work is increasingly hard to staff and expensive to get wrong. AI can already do much of this work today. It is just not in the hands of these businesses yet.
We think businesses will soon run themselves, and small businesses will be among the first. Today, we are thrilled to announce that a16z is leading Lassie’s $35 million Series A – and partnering with a team solving exactly this problem.
Lassie is building AI that runs small businesses, starting with dental practices. Co-founders Steijn Pelle and Frédéric Renken did not find this problem from a distance. After working in consumer fintech at Robinhood and Coinbase, Steijn learned from his own dentist, Dr. Kwon, how complex the financial administration of an SMB dental practice can be. He and Frédéric, who had built product at Superhuman and Uber, then worked inside Dr. Kwon’s office, processing payments by hand to understand the workflow from the inside.
This story is emblematic of how Steijn and Frédéric have approached building Lassie. Before writing a single line of code, they spent months talking to dentists, primary care doctors, and healthcare finance teams. Then they spent years building the infrastructure and integrations required for agents to operate directly within a practice’s workflow: reading insurance claims, reconciling payments, posting to the ledger, and flagging claims that need action. Lassie is not a copilot that creates more work for the practice to review. It does the work.
Lassie already works with more than 700 practices across 49 states, generates more than $10 million in annualized revenue, and provides practices with 250,000 hours of labor a year. Growth has come largely through referrals and inbound demand – a sign that customers are not just buying the product, but telling other practice owners about it. The most important benefit, customers say, is not simply doing the work faster. It is catching the underpayments, denials, and missing claims that used to slip through.
Dental is a strong first market because the pain is acute and the workflows are structured, repetitive, and high-value. But the larger insight is not dental-specific. Every small business is still held together by human labor: people answer phones, schedule work, hire and train staff, chase paperwork, collect payments, reconcile accounts, follow up on exceptions, and keep the business moving. The last generation of software gave businesses better tools. AI agents change the unit of value from software to labor. Lassie is starting with dental, but the broader opportunity is much larger: the small business that runs itself.
That is also why Lassie is difficult to replicate with a generic model alone. Running a small business is not one task; it is thousands of recurring workflows across customers, vendors, payments, forms, systems, and exceptions. The product has to understand the business, connect to the tools where work happens, know when to act, and know when to ask. Over time, the product learns from every completed workflow, building a knowledge layer that is difficult to recreate from scratch.
We are thrilled to partner with Steijn, Frédéric, and the Lassie team as they build toward one of the most important shifts in software: from tools that help businesses operate to agents that do the work. If you know someone that owns a dental practice, check out the product here – and if you’re interested in joining the team, check out their open jobs here.
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