These groups are known to back a handful of Searchers every year or so in a hybrid-Traditional / Accelerator role. They have mentors and resources available like Accelerators but not necessarily full-time and no big peer groups of Searchers to work alongside. Nor are they dedicated to Search; it's just an investment arm within the organization. They are typically longer-term than Traditional Search: family offices in particular don't care if you want to run the business you acquire for decades, as long as you're doing a good job. While they do provide salaries and equity along the lines of a traditional search fund they also provide unique financing, timelines, and opportunities that traditional investors and accelerators wouldn't consider. Some of them are only looking for operators and already have businesses they own or want to acquire, others are looking to mimic / create their own version of a search fund. You'll have to interview and learn about the opportunities each can offer.
Kingsway Financial Services Inc.
Double R Partners
Summit Partners
Copley Equity
Gemini Investors
Alpine Investors
New Capital Partners
Shore Capital Partners
Hunter Trust