# Open Types A Volume & Order Flow concept (Market profile / auction theory) in the LuxAlgo Library. ## What are Open Types? Open types are the Market Profile taxonomy for how a session begins, popularized by Dalton's auction-theory work. Four classic types are named. Open-drive: price drives hard directionally from the first prints and does not trade back through the open. Open-test-drive: the market first probes a nearby reference or the other side of the open, finds no business, then drives away in the opposite direction. Open-rejection-reverse: an initial move runs, gets rejected, and price comes back through the open. Open-auction: price rotates quietly around the open with no early conviction. The taxonomy comes from the Market Profile lineage: J. Peter Steidlmayer's work at the Chicago Board of Trade in the 1980s reframed each session as an auction, and James Dalton's Mind Over Markets (1990) codified the opening classifications traders still use. Dalton argued the open is uniquely informative because overnight inventory, news, and institutional participation collide in the first minutes, telegraphing other-timeframe intent before any structure exists. The types are ranked by the confidence they imply. A drive signals strong other-timeframe participation from the bell, and the open itself then serves as a reference that should not be revisited while the premise holds. An open-auction, especially inside the prior day's [value area](https://www.luxalgo.com/library/concept/value-area/), implies balance and a rotational session. Classifying the open early gives a working hypothesis for the day type long before the profile is complete. Open type is half the read; open location is the other half. The framework also grades where a session opens relative to the prior day: inside value, outside value but inside range, or outside the range entirely. A drive from beyond yesterday's range must find acceptance or snap back, unlike the same drive from the middle of value. With [relative volume](https://www.luxalgo.com/library/concept/relative-volume/) to gauge participation, type and location turn the labels into a usable morning hypothesis. ## How to identify open types on a chart Classification happens on a 1- to 5-minute chart in the first 30 to 60 minutes, against references prepared before the bell. 1. Before the open, mark the prior day's high and low, its value area and [point of control](https://www.luxalgo.com/library/concept/point-of-control/), and the overnight range. 2. A persistent move away from the opening print that never trades back through it is an open-drive; the stronger the opening [volume spike](https://www.luxalgo.com/library/concept/volume-spike/), the more trustworthy the label. 3. A probe to one side that finds no business, then reverses through the open with conviction, is an open-test-drive; the rejected probe becomes a strong reference extreme. 4. An early directional run that gets rejected and trades back through the open is an open-rejection-reverse, downgrading the day toward two-sided trade. 5. Quiet rotation on both sides of the open, most often inside the prior day's value, is an open-auction, arguing for a responsive, rotational session. 6. Give the label half an hour to firm up and check it against [volume delta](https://www.luxalgo.com/library/concept/volume-delta/) and [session VWAP](https://www.luxalgo.com/library/concept/session-vwap/): conviction opens hold one side of VWAP, auctions straddle it. ## How traders use it - As an early day-type handicap: drive and test-drive opens raise the odds of directional, elongated sessions, while an open-auction inside prior value points toward rotation between known references. - As a risk anchor: on conviction opens, trading back through the open price voids the premise, so the open doubles as a natural invalidation line alongside the initial balance extremes. - As confluence with continuation behavior: a drive open that then starts one-timeframing is the textbook trend-day profile, while a drive that stalls and rotates warns the label was wrong. - As half of the open-location matrix: an out-of-range open plus a drive is the strongest continuation read, while an out-of-range open that stalls sets up the snap-back toward old value. - As an execution filter: on drive opens traders favor pullbacks toward an [anchored VWAP](https://www.luxalgo.com/library/concept/anchored-vwap/) set at the open rather than fading strength, while open-auction sessions favor responsive trades at the edges of the developing [volume profile](https://www.luxalgo.com/library/concept/volume-profile/). ## Open types vs related concepts - **TPO Profile** (https://www.luxalgo.com/library/concept/tpo-profile/): The TPO profile is the whole session's story told in brackets; the open type is its first sentence. A profile needs hours to develop; the open type is available in the first half hour, which is why the framework bothers labeling it. - **Value Area** (https://www.luxalgo.com/library/concept/value-area/): Value area is a reference computed from a finished distribution; open types describe live behavior against such references. The two combine: an open-auction inside yesterday's value argues rotation, a drive away from it argues the market is leaving. - **Session VWAP** (https://www.luxalgo.com/library/concept/session-vwap/): Session VWAP is a running, all-day read of intraday control; the open type is a one-time classification made in the first minutes. Many traders let the open type set the hypothesis and use VWAP behavior to keep score on it. ## FAQ ### What are the four Market Profile open types? Open-drive, open-test-drive, open-rejection-reverse, and open-auction, conventionally ordered from most to least initial conviction. Drive opens move directionally at once; test-drives probe one side first, fail, and go the other way; rejection-reverses come back through the open; open-auctions rotate around it. Real sessions are messier than the labels, so classification involves judgment. ### Does an open-drive always become a trend day? No. The framework treats a drive as the highest-conviction open because other-timeframe players are active immediately, and it often precedes elongated sessions, but the market can still stall, balance, or reverse. The practical use is conditional: as long as price stays beyond the open, the directional premise stands; back through it, the label is void. ### How do I tell an open-drive from an open-test-drive? By what happens first. A drive leaves the open immediately; a test-drive first probes one direction, finds nothing, then drives the other way, trading back through the open en route. Both are high-conviction opens, and the test-drive's failed probe supplies a stop reference the pure drive lacks. ### What does it mean to open inside or outside the prior day's value area? Location measures how out of balance the market starts. Opening inside value implies overnight agreement and favors rotation; opening outside value or beyond the whole range implies something changed overnight, and the session's job is deciding whether new prices gain acceptance or reject toward old value. ### Does volume matter when classifying the open? Yes. The labels describe conviction, and conviction without participation is suspect: a drive on thin volume stalls far more easily than one with institutional weight behind it, so many traders require above-normal opening volume before trusting a drive label. ### Do open types apply to markets that trade overnight? The framework was built on pit-session opens and is applied today to the regular-session open, 9:30 AM ET on U.S. index products, where participation is deepest. The overnight session supplies references the open trades against rather than changing how it is classified. ## Related concepts - Initial Balance: https://www.luxalgo.com/library/concept/initial-balance/ - TPO Profile: https://www.luxalgo.com/library/concept/tpo-profile/ - Single Prints: https://www.luxalgo.com/library/concept/single-prints/ - Unfinished Auction: https://www.luxalgo.com/library/concept/unfinished-auction/ - Excess: https://www.luxalgo.com/library/concept/excess/ - Balance vs Imbalance: https://www.luxalgo.com/library/concept/balance-vs-imbalance/ - Rotation Factor: https://www.luxalgo.com/library/concept/rotation-factor/ - One-timeframing: https://www.luxalgo.com/library/concept/one-timeframing/ - Day-type Taxonomy: https://www.luxalgo.com/library/concept/day-type-taxonomy/ - Value Migration: https://www.luxalgo.com/library/concept/value-migration/ --- Source: https://www.luxalgo.com/library/concept/open-types/ (LuxAlgo Library, the encyclopedia of trading & technical analysis). Free to use with attribution: https://www.luxalgo.com/library/license/