Secondary Buyout — sale of a portfolio company from one PE sponsor to another (sponsor-to-sponsor sale), one of the five canonical PE exit routes. Sponsor buyers prices typically below strategic sales (no synergy value) but in competitive sponsor auctions the gap narrows. SBO process distinctions: faster diligence (pattern-recognized playbooks), more structured financing, less aggressive on price, greater focus on management team, often pre-negotiated rollover. The secondary-buyout phenomenon — businesses passing through 2-4 successive PE owners — is a structural feature of the industry, with each sponsor executing a distinct value-creation thesis (digitize → roll up → optimize → strategic exit).