Free Passive Float API — ETF Ownership Lock-Up
Index funds don't care about price. They buy or sell based on flows, not fundamentals. This API reveals how much of a stock's float is locked inside passive vehicles.
Endpoint
GET https://securitiesdb.com/api/v1/stocks/{ticker}/passive-floatWhy This Matters
As passive investing grows, more shares get "locked up" in index funds that never sell based on fundamentals. This reduces the effective float available for price discovery.
Stocks with high passive ownership may experience:
- Amplified volatility during index rebalances
- Reduced price discovery — fewer active investors setting prices
- Correlation spikes — stocks move with the index regardless of fundamentals
- Blind dollar flows — billions of dollars deployed with zero fundamental analysis
Response Fields
| Field | Description |
|---|---|
| passive_float.locked_pct | % of total shares held by tracked ETFs |
| passive_float.blind_dollars | Total market value held by ETFs (in USD) |
| passive_float.total_tracked_aum | Combined AUM of all ETFs holding this stock |
| top_etf_holders[] | Top 20 ETFs holding this stock, with shares, AUM, and weight |
Python Example
import requests
r = requests.get("https://securitiesdb.com/api/v1/stocks/NVDA/passive-float")
data = r.json()["data"]
pf = data["passive_float"]
print(f"NVDA passive lock-up: {pf['locked_pct']:.1f}%")
print(f"Blind dollars: ${pf['blind_dollars']:,.0f}")
print("\nTop ETF holders:")
for h in data["top_etf_holders"][:5]:
print(f" {h['etf_ticker']}: {h['shares_held']:,} shares ({h['weight_in_etf']:.2f}%)")