Reading the session
Gap up, gap down, and premarket change: which price are you comparing?
Learn how gap up and gap down are calculated, how opening gaps differ from premarket changes, and why the reference price and timestamp matter.
Articles
Related explainers
Data study
What Time Do Small-Cap Gappers Hit Their High of Day?
A look at 671 US stock gap-ups of 20% or more from July 1 to October 2, 2026: when the 4:00 a.m.–8:00 p.m. ET high printed, split by gap size, price and how the day ended.
Company disclosures
Offering, dilution, and reverse split: what is actually changing?
Understand stock offerings, dilution, and reverse splits. Distinguish new issuance from resale and check transaction stages before interpreting share counts.
Company disclosures
What is a shelf registration? Reading S-3 filings, ATMs and offering capacity
Learn what a shelf registration means in U.S. stocks. Separate S-3 capacity, ATM programs and actual sales; understand baby shelves and check SEC filings.
Retrospective data built after the session from stored records, with links to the original sources. Not real-time, not investment advice and not a recommendation to buy or sell any security.