Indices, Baskets, and Companies

The three types of markets available — PIX, sector baskets, and company indices.

Primi offers three levels of market exposure: a single index for the private market, sector baskets, and individual company indices. All three types are calculated using the same momentum methodology from bid-ask midpoints aggregated across independent secondary markets using our 100% reproducible methodology that’s outlined in these docs.

1. The Primi Index (PIX)

PIX is a single composite index measuring the aggregate momentum of the large private company ecosystem. It is calculated as an equal-weighted average of all listed individual company Primi indices where data quality meets the minimum threshold.

PIX launches at 100 and rises when the average listed company is beating its own momentum baseline, and falls when the average company is decelerating relative to its history. It is the pulse of the entire private market in one number.

2. Sector Baskets

Primi offers thematic sector baskets, each calculated as an equal-weighted average of the individual company indices within that sector. Each basket moves based on the collective excess momentum of its member companies relative to their individual 12-month baselines.

Basket	Example Companies
AI	OpenAI, Anthropic, Perplexity, Thinking Machines Lab, Cohere, SandboxAQ, Anysphere
Fintech	Stripe, Plaid, Brex, Ramp, Rippling
Space & Defense	SpaceX, Anduril, Physical Intelligence, Figure AI
Consumer	Fanatics, Discord, Epic Games, Canva, Impossible Foods
Data & Infrastructure	Databricks, Scale AI, Glean

Sector baskets allow traders to express a view on an entire theme — the AI sector accelerating or the fintech sector decelerating — without picking individual names.

3. Individual Company Indices

Each of the listed companies has its own continuous momentum index and updates daily.

The index measures whether that company’s secondary market bid-ask momentum is accelerating or decelerating relative to its own trailing 12-month baseline — not the absolute price level or the rate of appreciation in isolation.

• A rising index means the company is appreciating faster than its own recent history.
• A falling index means it is decelerating below its own baseline, even if the absolute secondary market price is still rising.

This structure creates a genuinely two-sided market for every listed company. Even the most obvious growing companies have uncertain near-term momentum relative to their own history.

Methodology

See exactly how each index is calculated.