FilingFirehose vs Polygon.io
Polygon is a market-data API (quotes, bars, options chains). FilingFirehose covers the SEC filings layer they don't parse.
Side-by-side
| Feature | FilingFirehose | Polygon.io |
|---|---|---|
| Primary scope | SEC filings, body-text-parsed | Real-time + historical market data, options, news |
| 8-K body classification | Yes (discrepancy_items + suspected_buried_events) | Filer-reported only |
| 13D / 13G with activist tags | Yes (21+ activists) | Filing reference only |
| ATM offering detection on S-3 / 424B5 | Yes (sales agent + shelf size) | No |
| Pricing | $29-$299/mo | $0-$199/mo for stocks tier |
| Best for | Compliance / quant / activist tracking on filings | Trading / charting / quote feeds |
When FilingFirehose is the right call
You want body-text-parsed 8-K items — including a flag for filings where the body language suggests a different item than what the filer reported. You're at the $29–$299/mo tier and don't need enterprise contracting.
When Polygon.io is the right call
You want a much broader form-type catalog beyond the 8-K / S-3 / 13D core, you're willing to pay enterprise pricing, and brand recognition matters for an internal tooling pitch.
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