You can cheaply detect SEC Filings many seconds to hours ahead of time again

In January 2025, I opensourced a way to detect SEC filings faster.

This relied on the ability to access SEC filings' index pages using just accession number without cik. e.g.

• https://www.sec.gov/Archives/edgar/data/000110465923015159/0001104659-23-015159-index.html (no cik)
• https://www.sec.gov/Archives/edgar/data/1318605/000110465923015159/0001104659-23-015159-index.html (cik)

On October 5th, 2026 sec.gov required cik to be in the url. I then published this article.

On October 23rd, sec.gov undid this change. Graph is from datamule-statistics.

You can try out Fastest SEC Filings Websocket for $0.25/connection/day. I aim to improve it to capture 50%+ of filings early.