Market maker or accumulation: telling one bot from another

2026-09-18

Spotting a bot in the tape is half the work. The other half is knowing what it wants — because the two most common bots want opposite things.

Two different animals

A market maker has no opinion on price. It quotes a bid slightly below and an offer slightly above at the same time and earns the difference. Its goal is turnover and a flat book by the end of the day. If the market moves, it shifts both quotes and keeps working.

Accumulation (or distribution) has an opinion and needs size. It buys and buys because it wants the coins, not the spread. Getting filled without lifting price is the whole problem, which is why the order gets sliced into equal pieces.

Four tells

1. Sides

The primary one. A market maker prints on both sides in roughly equal measure: buy — sell — buy — sell. Accumulation hits one side and holds the skew: nine buys out of ten. If over a two-minute window the side balance is near 50/50, it is a maker, whatever the sizes look like.

2. Who is the aggressor

Every trade has a resting side and a side that came to take it. A market maker is almost always passive: it sits, others come to it. Accumulation is more often active, lifting other people's orders. Nearly every exchange trade stream carries an "is buyer maker" flag — that is the field to read.

3. Behaviour on a move

Jerk the price and the maker vanishes for a second, then returns with a wider spread. Accumulation does the opposite: cheaper means take more.

4. Lifetime

A maker works around the clock, pausing on volatility, and is always there in the background. Accumulation is an event with a start and an end: half an hour, two hours, a day. Then it is over and does not come back.

Why confusing them is expensive

Mistake a maker for accumulation and you conclude "somebody big is buying" and go long. In reality nobody went anywhere: the maker bought from you and sold to the next person immediately. Price stays put, you paid fees and spread.

The reverse error costs more. You see steady buying, decide it is "just a maker, background noise," and ignore it. Meanwhile somebody accumulated two days of turnover — and an hour later price went where they were dragging it.

A third case: liquidity sweeps

Some bots neither accumulate nor quote — they push. A run of aggressive buys, fast, with no regard for average price. Usually stop runs or a flush ahead of a reversal. The tell is speed — a beat in tenths of a second — and the fact that price returns to nearly where it started afterwards. Accumulation never does this: paying for your own ramp defeats the purpose.

Practical use

• One-sided accumulation and price is not moving — look for who is supplying it above: an iceberg or a plain wall. Trade whoever runs out first.
• A market maker is not a signal at all. It is liquidity, nothing more.
• A sweep is not something to chase at market. Wait for the run to end — price usually gives back half the move.

How software separates them

All of the above is arithmetic over a window of trades: side ratio, aggressor ratio, uniformity of size and beat, duration of the run. A person can compute that for one coin; software does it for a thousand pairs across a dozen exchanges at once and hands you a card — exchange, coin, side, speed, size. The decision is still yours.

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