Meaning and transaction use
An SEC-filed fund prospectus defines SOM as the percentage of the serviceable available market a company can realistically capture based on its business model and target consumers. [S1]
An SEC-filed company presentation constrains SOM through facility production capability, illustrating an operational capacity basis. [S2]
Proposed control method: reconcile top-down market estimates with a bottom-up customer, channel and capacity model.
Worked example
Illustrative annual SOM only. Assume 50,000 reachable customers, supportable penetration of 8% and annual revenue of 2,500 per captured customer.
Scroll the table horizontally to view all columns.
| Measure | Calculation | Result |
|---|---|---|
| Reachable customers | Given | 50,000 |
| Captured customers | 50,000 x 8% | 4,000 |
| Revenue per customer | Given | 2,500 |
| Illustrative SOM | 4,000 x 2,500 | 10.0m |
The illustrative annual SOM is 10.0 million under the stated reach, penetration and price assumptions.
Proposed transaction review process
Define SAM
Set segment, geography, channel, use case and period.
Model constraints
Quantify reach, conversion, capacity, competition and price.
Build bottom-up SOM
Calculate customers, units and revenue by channel and period.
Validate and update
Compare actual pipeline, wins, churn and capacity with assumptions.
Evidence checklist
Market
Source, date, segment, geography and demand basis.
Reach
Target accounts, channels, sales capacity and qualification.
Conversion
Funnel, win rates, adoption, retention and implementation limits.
Economics
Price, units, capacity, gross margin and timing.
Decision framework
| Situation | Proposed action |
|---|---|
| Top-down and bottom-up estimates diverge | Use the constrained bottom-up case and explain the gap. |
| Capacity limits growth | Model investment, lead time and unit economics. |
| The category is new | Use scenario ranges and adoption evidence. |
| Pipeline quality changes | Refresh capture assumptions and forecast timing. |
Common errors to check
- Applying an arbitrary share to TAM.
- Ignoring sales and delivery capacity.
- Mixing customer counts with revenue.
- Presenting management estimates as observed market facts.
Build a bottom-up obtainable market
Bring the segment definition, pipeline, channel capacity and pricing assumptions to a SOM review. Reconcile market estimates with executable growth capacity.
Discuss the transactionPrimary references and editorial scope
- SEC filing: SOM definition
Definition of SOM as the realistic portion of SAM based on business model and target consumers. Reference checked 17 September 2026. - SEC filing: Capacity-constrained SOM
Example SOM constrained by production-facility capability. Reference checked 17 September 2026.
General transaction education using public United States filings. Figures are hypothetical. SOM is an estimate requiring sourced market data and verified company assumptions.
General business information. Obtain advice appropriate to the legal, tax, accounting and financing facts. No offer, lender commitment or transaction outcome is represented. All worked examples use expressly assumed figures. Editorial draft date: 17 September 2026.
