Research Desk · Magnitude relative to a market model; not a forecast and not a direction.
How large the move was around each SEC filing
How much a ticker moved around earnings dates and SEC filings (company 8-Ks, insider Form 4s, ownership stakes and offerings), compared with a market model and with random dates of the same tickers. Absolute size only, never the direction. When a kind of event looks no different from a random day, the row says so.
REAL EXAMPLE · LATEST SEC FILING IN THE EVENT STUDY
AAPL · Company filings (8-K) · 8-K 2.02 · Earnings release · 2026-11-02 · View on sec.gov ↗
Public, no login: the latest SEC filing in the event study, with its date and source.See a ticker page with its latest event →
What a row shows
SAMPLE ROW
Offering filing · 424B5 · n = 412 · |CAR| median 3.1% · range 1.6× · volume 2.2× · Larger than on random dates
Illustrative figures, not a measured row. In the dashboard each row carries its own n, interval and verdict.
Size, never sign
|CAR| over sessions −1 to +5, the event-day range and volume against the median day of the estimation window.
Against random dates
Each kind of event is compared with random dates of the same tickers: “Larger than on random dates” or “Indistinguishable from random dates”.
Sample size on every row
Fewer than 100 events: an early sample without an interval. Fewer than 30: not shown.
Source per event
Each event links to its SEC filing. The filing list exports as CSV on Elite; price measures are not in the file.
HOW THIS IS CALCULATED
Expected moves come from a market model fitted on the 120 sessions that end 10 sessions before the event, against SPY or the sector ETF of the company’s SIC code. |CAR| is the absolute size of the cumulative abnormal price change over sessions −1 to +5. It has no sign. Range × and volume × compare the event day with the median day of the estimation window. One event per ticker and day. With fewer than 100 events the row is an early sample without an interval; below 30 it is not shown. In the aggregates, only the first event of each run counts (no other event of the same kind in the previous 7 sessions); the ticker view shows every event and marks the ones that follow an earlier one. Pro shows the last 30 sessions; Elite shows the full history.
Frequently asked questions
What does the Event Study measure?
How large the price move, the trading range and the volume were around each kind of event, compared with what a market model expected for the same stock. The price measure is |CAR|: the absolute size of the cumulative abnormal change over sessions −1 to +5. It has no sign.
Does it say whether a stock goes up or down after an event?
No. Every measure is a size, in either direction. A larger-than-usual move after a filing says nothing about which way the stock moved or will move. We publish no direction on any page; the reasons are on the page about why we do not predict direction.
What does “Indistinguishable from random dates” mean?
Each kind of event is compared with random dates of the same tickers. When the event-day sizes are not larger than those random dates by more than a 5% margin, the row says so. That is a result, not a missing value: many filings come with moves of ordinary size. A verdict decided within 1 point of that margin is marked Borderline.
Which events are covered?
Earnings dates and SEC filings: 8-K company filings by item, 13D ownership stake filings, Form 4 insider filings and offering filings (registration statements and prospectuses), each with its date and a link to the source. One event per ticker and day. Rows with fewer than 100 events are labeled as early samples, and rows with fewer than 30 are not shown. By default the verdict leaves out events with an earnings release in their window; the verdict including them is shown next to it.
What can I see without an account?
Every ticker page shows the latest SEC filing in the event study, with its date and a link to sec.gov. The size of the move, range and volume around each event is in the dashboard on the Pro plan.
See how large the moves were, not which way
The Event Study is in the Research Desk on the Pro plan.
Not financial advice. Trading involves risk. TradeAI News provides structural market context, not directional recommendations.
Last updated October 28, 2026