Sum of the Parts
Valuing each business within a company separately and adding them up. Useful where the parts deserve different multiples, and dependent on disclosure that may not exist.
MadStockAlerts Research · Updated August 28, 2026
What to take away
- Each segment is valued on a multiple appropriate to its own business.
- It requires segment disclosure, which sets the limit on how far it can go.
- Corporate costs and net debt are deducted from the total.
- A conglomerate discount is frequently applied and is contested.
- The method is most used where a separation is plausible.
MAD Academy Training Video · 0:46
Valuing the Pieces Separately
Sum of the parts values each business on its own multiple, and the gap to the market price is usually a discount rather than a mistake.
This lesson is part of a Stock Alerts + Tools plan.
The construction
- 1Take each reported segmentUsing the disclosed revenue and profit measure.
- 2Apply a multiple appropriate to that businessDrawn from comparable standalone companies.
- 3Add the valuesProducing a gross enterprise value for the operating businesses.
- 4Deduct unallocated corporate costsCapitalised at a multiple, since they are ongoing.
- 5Deduct net debt and other claimsWhich converts enterprise value into equity value.
Step four is the one most often omitted, and omitting it inflates the result. Corporate overhead is a real recurring cost and belongs in the calculation whether or not it is allocated to a segment.
Where it is worth doing
The method earns its complexity where the parts are genuinely different businesses that would attract different multiples. A company combining a slow-growing industrial division with a fast-growing software one is not well described by a single multiple.
- Software segmentValued on a software multiple
- Services segmentValued on a services multiple
- Industrial segmentValued on an industrial multiple
- - corporate costsCapitalised, since they recur
- - net debtWhich converts enterprise value into equity value
The disclosure constraint
The analysis can only be as granular as the segment reporting allows. A company reporting one segment cannot be valued this way at all, and a large unallocated other line limits how much of the total the analysis actually covers.
Segment profit is also defined by management and may exclude corporate overhead entirely, which means the segment margins used are not comparable to a standalone company's. That is the same limitation the segment reporting article describes, and it binds every sum-of-the-parts calculation.
The conglomerate discount
Diversified companies frequently trade below the sum of their parts. The gap is described as a conglomerate discount and several explanations are offered for it.
- Capital may be allocated between divisions less efficiently than markets would allocate it.
- Complexity reduces the number of investors willing to analyse the company.
- Segment disclosure is less informative than standalone reporting.
- Or the sum-of-the-parts calculation is simply too generous, which is the least flattering explanation and is sometimes the right one.
The last item is worth taking seriously. A method that reliably produces a value above the market price should prompt a check of the multiples used before it prompts a conclusion about the market.
When the market forces the question
The analysis becomes more than an exercise when a separation is actually plausible, because at that point the parts might genuinely be valued separately by the market.
| Situation | Why the analysis matters |
|---|---|
| An announced spin-off | The parts will trade separately, so the sum becomes testable |
| Activist pressure to separate | The 13D will frequently argue precisely this case |
| A segment being sold | One part is being valued in a transaction |
| A persistent discount with no explanation | Either the analysis is too generous or the market is missing something |
The second row connects directly to the Schedule 13D article. Item 4 of an activist filing frequently sets out a sum-of-the-parts argument explicitly, which makes it one of the few places the analysis is published rather than performed privately.
A separation also imposes costs the analysis usually omits: duplicated corporate functions, transaction expenses, and the loss of any genuine synergies. Those are real and are the counterargument the company itself will make.