Truman Sachs launches Cubby, an AI teaching assistant for law students targeting a $1B market
Aug 25, 2025 with Truman Sachs
Key Points
- Truman Sachs launches Cubby, an AI teaching assistant that trains on individual professor syllabi and past exams to replace Quimbee, the dominant $30/month study tool used by 120,000 US law students annually.
- Cubby targets a $1 billion market by expanding beyond law school into LSAT prep and bar exam study, betting that student workflows lock in early and carry into Big Law careers.
- A major bar prep company sent a cease-and-desist alleging Cubby trained on its materials; Sachs countersued on anticompetitive grounds and the matter was dropped, signaling incumbent vulnerability in legal education tech.
Summary
Truman Sachs has launched Cubby, an AI-powered teaching assistant targeting the roughly 120,000 law students enrolled annually in US law schools. The product is positioned as a direct replacement for Quimbee, a legacy study tool launched in 2007 that currently charges $30 per month and commands wide adoption across the student population. Sachs describes Quimbee as essentially static CliffsNotes for case law, arguing the substitution case for Cubby will be self-evident.
The product is trained on thousands of practice exams and case briefs authored by a recent Georgetown Law graduate. Its core experience mirrors a Duolingo-style adaptive course, calibrated to a student's specific professor and curriculum, with unlimited practice final exams, instant grading, and feedback. The professor-specific focus is deliberate: in curve-based law school grading, rank determines access to Big Law first-year salaries of roughly $220,000, making students highly motivated to spend on performance tools.
Sachs sizes the addressable market at approximately $1 billion, based on 120,000-plus students spending an average of $5,000 on supplemental education tools across a five-year window from LSAT through bar prep. He identifies LSAT and bar preparation as the next logical expansion beyond the law school segment.
The go-to-market strategy leans heavily on campus activation. At launch, Cubby deployed a branded cafe truck outside Cardozo Law School, distributing free coffee, bagels, and ice cream to students. Sachs frames the longer-term strategic thesis around distribution and customer relationship lock-in, drawing a parallel to how Google Docs became entrenched in enterprise workflows by being adopted first in academic settings.
The company has already encountered incumbent resistance. Shortly after a early TikTok post, a major bar prep company that had recently been acquired sent a cease-and-desist alleging Cubby may have trained on its materials. Sachs says the team responded by threatening a countersuit on anticompetitive grounds, and the matter appears to have been dropped. The episode signals the competitive sensitivity of the space and the leverage established players believe they hold.
Sachs is not framing this as a venture-scale moonshot in the near term. The immediate priority is establishing a defensible foothold in legal education, with the bet that today's law students become tomorrow's Big Law associates and partners, carrying Cubby's workflow habits into the broader legal tech market where barriers to entry, specialized model requirements, and incumbent relationships make organic penetration difficult.