Markets & trading
The market open and close are rule-based transition points, often set through auctions that combine orders into a single clearing price. They are not merely the first and last random trades.
Make it click
An auctioneer collects buy and sell interest before choosing the price that can match the most compatible quantity. That process differs from one buyer meeting one seller.
Now put that into markets
Opening and closing auctions concentrate liquidity and establish benchmark prices. Continuous trading surrounds them under different matching rules.
Imbalances, order cut-offs and venue procedures affect auction outcomes. Index funds and institutions often trade near the close to match official benchmarks.
Identify the venue's official open or close field and auction status. Separate an auction price from extended-hours prints nearby in time.
Auction concentration can create sharp moves and a benchmark price is not guaranteed for every order. Halts and special opens can alter the normal sequence.
Takeaway
