Industry Sourcing / Research

My fund is heavy on top-down niche industry thesis investing. Essentially, most of our investments have come from finding an niche industrial industry that we really like (good competitive dynamics, long-term price growth, fragmented market, high barriers to entry, etc.) and investing in the industry leader to be a consolidator or adding value elsewhere. Historically, finding these industries have come from finding a CIM of a competitor or supplier/customer, not liking that company, but liking the industry dynamics, and performing further industry research work to identify targets in the industry that we do like.

This can be a like finding a needle in a haystack. I'm curious if any other private equity funds or their Business Development partners have any good methods or sources for sourcing interesting niche industries other than CIMs or prior operating partner/deal knowledge, particularly in the industrials umbrella. 

Any help or ideas are greatly appreciated