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How announcement_time (BMO/AMC) is inferred from 8-K acceptance time

The announcement_time field on each earnings row indicates whether the company likely announced results before the market open (BMO) or after the close (AMC). It is derived from the SEC acceptance timestamp on the matched Item 2.02 8-K filing — not from press-release text or company IR pages.

Matching the 8-K to a quarter

For each fiscal quarter, Aegwah searches the company's recent 8-K and 8-K/A filings and selects the nearest 8-K filed within 60 days after the fiscal period end. If no 8-K matches, the field falls back to unknown and announcement_date uses the 10-Q/10-K report date instead.

Classification rules (US/Eastern)

The SEC acceptanceDateTime on the matched 8-K is converted to US/Eastern and classified:

• BMO (before market open): acceptance before 09:30 ET.
• AMC (after market close): acceptance at or after 16:00 ET.
• unknown: acceptance between 09:30 and 16:00 ET (intraday), or when no acceptance timestamp is available.

Newer SEC submissions use ISO UTC timestamps (e.g. 2026-07-02T13:23:16.000Z); older payloads may use wall-clock strings treated as Eastern.

What this field is and is not

announcement_time is a data field describing when the SEC accepted the earnings 8-K relative to regular trading hours. It is useful for aligning earnings data with price history and understanding same-day vs. next-day market context. It is not a trading signal or recommendation.

Limitations

• Some companies file the 8-K before the actual press release hits newswires — acceptance time approximates, but does not perfectly match, the moment the market learns the number.
• Intraday filings (09:30–16:00 ET) are classified as unknown because they could be pre-release SEC filing or a same-day announcement during trading hours.
• Companies that announce via 10-Q/10-K without a separate 8-K may lack a BMO/AMC label entirely.

The announcement_time field is included in the paid dataset and the free sample ZIP.

Research / data documentation only. Not investment advice. Aegwah is a dataset product.