# ADR-0004: Shared market cache with multi-tenant fetch dedupe

Date: 2026-06-27
Status: Accepted

## Decision
Public market data (price, filings, ownership snapshots) is shared across all users. The adapter queue dedupes concurrent cache-misses from multiple users into a single fetch.

## Consequences
- Rare public-data fetches; private user data isolated by ownerId.
- Staleness windows per data class (live quote 1min, daily OHLCV permanent, filings immutable forever, 13F per-quarter immutable).
- Report runner reconstructs from cache only; no live calls.