The Accumulator Angel Fund was created to help angel investors diversify their portfolio and distribute risk across multiple assets with lower volatility, creating a safer investment option.

Angels can join the fund by exchanging their company shares or by investing cash.

In exchange, they receive the equivalent value of the Accumulator fund, becoming investors in category-leading companies by leveraging their capital or the value of their equity.

Every time one of the portfolio companies enjoys an exit, all members cash out a pro-rata share.

our mission

We are on a mission to accumulate the world's top business angels into a global alliance, all driven by a mutual interest in each other's success. We are a community-owned fund of experienced angel investors, sharing knowledge and our extensive networks.

Oskar Hartmann
Founder and Managing Partner

Oskar Hartmann

Oskar Hartmann is a serial entrepreneur, philanthropist, and veteran unicorn angel investor with over 100 companies, 20+ nonprofits, and 14 unicorns in his investment portfolio. He has founded five companies in Germany and CEE, achieving three successful exits, and initiated a charitable foundation focused on children’s education.

Oskar holds a world record in rowing and is an avid cyclist. A family man, father, and global citizen, he speaks three languages fluently. His mission is to build the world’s first community of top global business angels, helping them diversify risks and expedite liquidity returns.

Arete Index

Highlighting the World's Most Value-Creating Angel Investors
The 2024 Arete Index is the world’s most comprehensive list of angel investors, featuring the top 1,000 angels who are adding the most value to the startup economy.
Angel investors play a pivotal role in the global startup ecosystem by providing essential early-stage capital when the risk of failure is high and traditional investors are hesitant. These individuals assume significant risk, bridging the gap in preliminary funding, and driving innovation and economic growth. In 2023, angel investors in the U.S. alone funded over 19,000 startups with a total investment of over $30 billion. Despite their critical contributions, the invaluable support of angel investors often remains unseen by the public.
Oskar Hartmann, Founders Forum Group, and the Accumulator Angel Fund joined forces to build the 2024 Arete Index, to celebrate angels worldwide and highlight the significant value they bring to the global economy.

The Arete Index evaluates angel investors by considering numerous factors, including the number, amount, and success of an angel’s investments, their ability to support startups beyond their financial assistance through network introductions, mentoring and coaching, and finally, the investor's impact on the growth and development of their invested companies.

Accumulator is a U.S. private equity firm that manages U.S. investment funds under the regulatory authority of the U.S. Securities and Exchange Commission.  The investment fund function similarly to an index-like fund that covers the broad market of privately held growth-stage tech companies.

Accumulator is structured as a Delaware limited partnership and undergoes an annual audit by weaver.

We collaborate closely with legal and tax advisors to tailor the deal structure to meet the specific needs of our founders. Our approach ensures personalized and tailor-made solutions, leveraging expert advice for optimal results.