Sachin Dev Duggal, founder of the now-defunct Builder.ai, is preparing to launch a new AI-focused startup named SecondBrain, months after stepping down as CEO of Builder. The announcement comes following Builder.ai’s collapse into insolvency amid allegations of inflated sales and revenue projections. Duggal has reportedly briefed investors on the new venture, signaling his continued focus on pioneering developments in artificial intelligence.
In a statement to Sifted, Duggal explained that SecondBrain will concentrate on neurosymbolic AI, an approach that integrates neural networks with symbolic reasoning to create more effective AI systems. He also clarified misconceptions in media reports, emphasizing that the startup will not be aimed at helping businesses build software. Duggal said, “My early work in neurosymbolic AI is a spectrum away from this,” highlighting the technical and research-driven nature of the project.
SecondBrain marks Duggal’s fourth entrepreneurial venture, following Builder, Nivio, and Shoto. Builder.ai, once considered one of Britain’s most promising AI startups, raised over $500 million from prominent investors including Microsoft and the Qatari Investment Fund before Duggal’s departure in March 2025. The company’s US entity later collapsed as creditors seized funds after provisional accounts revealed significant reductions to previously reported revenue estimates.
Duggal’s move to focus on neurosymbolic AI reflects a broader trend in the AI sector, where startups are exploring hybrid approaches that combine deep learning with symbolic reasoning to address limitations of conventional neural network models. Analysts suggest that ventures like SecondBrain have the potential to advance AI capabilities beyond current industry applications, creating more interpretable and robust systems.
With his track record of founding multiple startups and attracting investor attention, Duggal’s new initiative is poised to garner interest from the AI research and investment community. As he embarks on this latest journey, SecondBrain represents a technical pivot from his previous ventures, emphasizing research-driven innovation over commercial software offerings.
By leveraging neurosymbolic AI, Duggal aims to contribute to the next generation of artificial intelligence systems while rebuilding his entrepreneurial reputation after the turbulent closure of Builder.ai.
