Borja Martinez Rosa

Borja Martínez de la Rosa is a Founding Partner of Abac Capital, the Barcelona-based mid-market private equity firm he co-founded in 2014 alongside Oriol Pinya and Javier Rigau. Before launching Abac, he spent 13 years at Apax Partners, where he was a Partner on the global tech & telecom team and covered the Spanish market from 2004. Earlier in his career he was a Summer Associate at Goldman Sachs and an Associate at The Boston Consulting Group. He and his Abac co-founders were involved in launching several notable Spanish businesses over their careers, including Jazztel, eDreams, and Vueling.

He holds a degree in Business Administration from ESADE in Barcelona and an MBA from Harvard Business School, which he attended as a Fulbright Scholar.

In February 2018, Martínez de la Rosa helped launch Abac Nest, Abac Capital's early-stage vehicle, to close what he called the "gap of professionalized investment in the seed phase" in Spain. The initiative pairs Abac's venture-capital professionals with a network of around a dozen established entrepreneurs — including Rubén Bonet, co-founder of antenna-technology company Fractus, with whom Martínez de la Rosa formally established Abac Nest Ventures in 2017. Within the broader group, Martínez de la Rosa sits on the investment team for the Abac Nest II fund, alongside Joan Pina Ollé (who leads day-to-day investing), Oriol Pinya, and Federico Conchillo.

• Backs early-stage (pre-seed and seed) Spanish technology startups with the potential to scale internationally; roughly two-thirds of the Abac Nest portfolio is B2B SaaS.
• Sector emphasis on AI/software, fintech, digital health, and consumer; Abac Nest II is described as focusing on AI applied to solving real business problems.
• Check sizes of €200k–€1M in Abac Nest II (pre-seed/seed), up from the original Abac Nest's €50k–€100k initial tickets with capacity to follow on to ~€200k alongside VCs, family offices, and angels.
• Highly selective deal flow: the Abac Nest team reports seeing 120+ deals a month with an investment rate under 1%.
• Value-add pitch centered on the firm's network: "We are proud of our distinctive VC strategy, focused on adding value to Founders through our extensive network." In his own words on the seed strategy: "we are very excited to contribute to closing the gap of professionalized investment in the seed phase."