At MUUS, we are passionate and engaged investors.


The MUUS Investment Portfolio is designed to be an “all-weather” portfolio that captures exposure from several, long-tailed investment themes we believe offer excellent long term risk/reward profiles. In determining the best investment exposure to our highest conviction thematic focuses, we wed this “top down” approach with rigorous “bottom up” analysis. The MUUS Investment Portfolio employs a broad mandate to potential investment selection which includes growing our own operating companies, allocating capital to fund managers (hedge fund, long-only, PE, VC) as well as making our own direct investments in public equity, private equity, real estate, and private debt opportunities. Our portfolio investment methodology demands rigorous underwriting and seeks to partner with aligned counter-parties where long term relationships can be forged.

MUUS Climate Partners invests in high-growth companies that have the potential to address the challenges of climate change. Specifically, we focus at the convergence of advanced technology and decarbonization, to find highly scalable climate solutions with outsized impact.

Climate Partners Portfolio Companies:

 40 Years Of Entrepreneurship:

MUUS has grown from the long and successful careers of Michael Sonnenfeldt and his associates. Here are four examples that demonstrate MUUS's patient, hands-on approach honed over decades.