Lukas Walton, the billionaire grandson of Walmart founder Sam Walton, is reinventing the family office — building a multi-billion-dollar funding machine that powers charities, tech start-ups, public companies and activists seeking global change. Walton, 36, last year launched Builders Vision, a one-stop-shop of impact investing based in Chicago with more than $4 billion in assets. While most family offices separate philanthropy and investing, Walton has stitched them together into an impact-investing superstore – funding social and environmental causes through start-ups, public companies or charities. The Builders Vision venture capital fund, called S2G, is in the top quartile of venture capital funds by returns, according to Cambridge Associates benchmarks. Climate change, the food supply and ocean health are, after all, also investment risks, he said.

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