The Buy-and-Build Spread

What the model assumes

A platform is bought at one multiple and add-ons are bought at a lower one. The gap is captured at exit, when the combined business is valued as a single larger asset. The return in the model comes substantially from that arithmetic, and only partly from what the businesses do after they are joined.

The arithmetic holds on one condition: that a supply of add-ons exists which will clear at the lower multiple, in the size the model wants, over the hold period. The model rarely tests that condition. It is written as an assumption about the market and treated as a fact about the plan.

The set is finite and it is shared

Inside a defined thesis and geography, the number of companies of the right size, in the right sub-sector, with an owner of the right age is countable. Often it is a two-figure number. It does not grow during the hold period.

Every sponsor pursuing that thesis is working the same list, and so is every strategic. The list circulates. Advisers assemble it for whoever asks, which means the set is not a source of advantage to anyone holding it — only to whoever reached its members first.

The owners on the list learn as well. An owner who has taken three approaches in eighteen months knows there is a bid, knows roughly its shape, and prices accordingly. The discount that the model assumed was structural turns out to have been a function of nobody having called yet.

Where the spread actually decays

The first add-on is usually the cheapest and the fastest, because it comes out of the platform's own network. The founder has known that competitor for twenty years, the conversation predates the sponsor, and the terms reflect a relationship rather than a market.

The second does not come from there. By then the network is spent, and the sponsor is buying from people the platform's management has no history with. Multiple paid drifts up. Time to close extends. The programme slows at the exact point the underwriting assumed it would accelerate.

A stalled buy-and-build is expensive in a way the model does not price. Capital sits, the platform carries the cost of a structure built for a group it does not yet have, and the exit narrative reverts to the operating performance of a single company.

What holds it open

Continuous coverage of the whole set, held from before the platform is bought and maintained through the hold, changes which owners are reachable at which moment. The owner who sells at the lower multiple is the one who was in conversation before the platform existed and before three other sponsors called.

That is a different activity from a search that begins when the platform closes and the integration team asks for a pipeline. It runs on a different clock, and it has to be funded before there is anything to point at.

The work sits between the first and second acquisition, and it has to have started before the first.