Mac Liu isn’t a lawyer, but he knows how to build a tech startup. The two-time founder is betting that edge will separate his new law firm from a crowded field of neofirms.
Liu’s startup, Arceus, combines a law firm staffed by attorneys with software built to speed up contract review. The company says it can shrink the time it takes to review a standard agreement from days or weeks to a few hours. If a review takes more than eight hours, it’s free.
On Thursday, Arceus said it raised new funding led by Greycroft, bringing its total funding to $17 million. Craft Ventures and South Park Commons also participated.
Before Arceus, Liu worked in tech roles at Robinhood and Anduril. He later started Vultron, which built software for defense contractors. Earlier this year, he sold the company to a govtech firm, pWin. In the deal, pWin took Vultron’s customer base, and Liu kept the cash. He’s now recycling that money into Arceus.
The model is similar to one popularized by Crosby, which builds software for its own lawyers, and was most recently valued at $400 million. The bet is that in-house legal teams don’t want another tool to manage; they want the work done faster.
Rather than requiring customers to log into another platform, Arceus lets employees submit contracts for review directly from Slack. A virtual agent gathers context from systems such as Salesforce and HubSpot, as well as from past agreements, suggests changes, and then routes the matter to one of the firm’s attorneys for final review.
Liu says he has tried to build Arceus less like a law firm and more like a startup. He hired engineers before his first lawyer. Employees work together in the office six days a week. Liu wants every customer request acknowledged within five minutes, though he said Arceus isn’t there yet.
“You’re not pinging a lawyer because you just want to chat,” Liu said. “You’re nervous about something, you’re questioning something, and you want to feel like someone’s there.”
Some of the best-funded neofirms were started by in-house lawyers. Crosby founder Ryan Daniels previously worked as a fractional general counsel. Vector Legal’s Mitch Duncombe was a lawyer at Y Combinator. Their own software reflects years spent doing the work.
Liu argues the real competition isn’t other AI-native law firms. Instead, he sees the company taking share from three places at once: traditional law firms, in-house legal teams, and the software companies that sell tools to corporate lawyers.
Someday, he says, customers that hire Arceus may need fewer internal lawyers — a lofty goal at a time when most legal departments are still figuring out where AI belongs.
Investors, at least, are buying into that vision.
Read the pitch deck Arceus used to raise its Series A.
