Sphere was founded to rebuild global indirect tax compliance from the ground up using AI. Where legacy tax engines rely on armies of human researchers to track changing sales tax, VAT and GST rules, Sphere built TRAM (Tax Review and Assessment Model), a model trained on thousands of hours of expert tax-researcher feedback that continuously collects, codifies and monitors global tax law and rates.
The platform automates the full indirect tax lifecycle: determining where a business has tax obligations, registering with authorities, calculating the correct rate at transaction time, and filing and remitting through direct rails into 100+ tax authorities. Experts remain in the loop to validate TRAM outputs and continually improve accuracy.
Sphere has become a core compliance layer for fast-scaling, globally distributed software companies that hit cross-border tax complexity earlier than ever. Customers include Lovable, Replit, Windsurf, Deel and ElevenLabs.
Following its Series A, Sphere is expanding TRAM beyond indirect tax into input tax, withholding, e-invoicing and tariffs, with the goal of becoming a full revenue-based compliance engine for modern finance teams.
The company is backed by Andreessen Horowitz, Y Combinator, Felicis and 20VC, and is hiring engineers to extend its AI-native tax engine.