> ## Documentation Index
> Fetch the complete documentation index at: https://docs.shovels.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Industry Classification Data (NAICS & SIC)

> Understand NAICS and SIC industry classification codes in Shovels contractor data, their sources, and limitations.

Shovels includes industry classification data for contractors, though this data has important limitations to understand.

## Available Classification Fields

| Field                 | Description                                         |
| --------------------- | --------------------------------------------------- |
| **NAICS**             | North American Industry Classification System codes |
| **SIC**               | Standard Industrial Classification codes            |
| **Primary\_industry** | General industry classification                     |

## Data Sources

Business industry classifications come from self-reported data, typically through:

* Business registration
* Insurance-related transactions

## Important Limitations

### Self-Reported Nature

Classifications are self-reported by businesses, not verified by Shovels.

### Broad Categories

Classifications are quite broad and may not precisely reflect a contractor's specialization.

### Multiple Classifications

Companies in higher-risk occupations often use multiple industry identifiers to reduce their workers' compensation insurance liability.

### No Central Authority

There is no central authority governing these categories.

<Warning>
  The Primary\_industry field should be taken with a grain of salt due to these limitations.
</Warning>

## NAICS vs SIC

| System    | Description                                    |
| --------- | ---------------------------------------------- |
| **NAICS** | More modern and specific classification system |
| **SIC**   | Older system, but more widely adopted          |

Both are included in our data because NAICS isn't as widely adopted as SIC codes.

## Better Alternatives

For understanding what a contractor actually does, consider:

* **Permit descriptions** - What work they've actually permitted
* **Tags** - Shovels-assigned categories based on permit data
* **Permit history** - Patterns of work they've completed

## Related Articles

* [Contractor data overview](/docs/knowledge-base/data/contractors/contractor-data-overview)
* [Contractor search](/docs/knowledge-base/api/contractors/contractor-search)