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

# Data Sources

> Source platforms, data collection, and the filters applied for the index.

## Source platforms

The Primi index for each company is calculated from bid-ask quotes collected across five eligible secondary market platforms:

* **Forge**
* **Hiive**
* **Nasdaq Private Market**
* **Caplight**

These platforms are independent of each other and of Primi. No single platform can represent more than **40 percent** of the composite reference price. This cap ensures that the index reflects a genuine cross-platform consensus rather than activity on any single venue.

## Data collection

Quotes are collected every **15 minutes** throughout the trading day. For each platform and each listed company, the best bid and best ask are recorded and used to calculate a per-platform midpoint:

```
Midpoint_platform = (Best_Bid + Best_Ask) / 2
```

Midpoints from all eligible platforms are then averaged with equal weight to produce the composite reference price.

## Staleness filter

Any quote not updated within the trailing **30 days** is excluded from the composite calculation. Stale quotes do not represent current market conditions and would distort the reference price if included.

## Sanity filter

Any platform midpoint more than **30 percent** away from the most recent verified transaction price on that platform is excluded. Verified transactions — actual completed trades — serve as calibration anchors for quote data. A quote far outside the range of real transactions is treated as unreliable.

## Anti-manipulation filter

Any quote movement that would shift the composite reference price by more than **10 percent** in a single 15-minute interval is flagged and held for 48 hours. It is incorporated only if a subsequent independent quote or verified transaction on a different platform confirms the new price level.

This prevents any single platform from moving the index meaningfully without independent corroboration.

## Verified transactions

In addition to bid-ask quotes, verified completed transactions from eligible platforms are used as calibration anchors for the sanity filter and as confirmation signals for the anti-manipulation filter. Transaction volume also factors into the eligibility criteria for listing and continued inclusion.

## Index immutability

Index values are immutable once computed. Once a 15-minute interval closes and the composite is calculated, that value is permanent and becomes part of the historical record used in future baseline calculations.