Two bots trading for the same Coinbase Exchange user can cancel each other's orders without trading with each other.
Coinbase's existing self-trade prevention rules apply when that user's orders cross. The newer order's prevention setting takes precedence. For two limit orders, the default cancels the smaller order and reduces the larger by the same size. Equal-sized orders are both cancelled.
That matters if one bot is maintaining quotes while another sends a limit order priced to trade immediately. The incoming order can remove or shrink a resting quote rather than fill against it.
Before running those strategies together, choose which order should survive that collision. Coinbase offers settings to cancel the oldest order, the newest order, or both. “Cancel newest” preserves the resting order; “cancel oldest” removes it and lets the newer order continue trying to execute. Check the setting on the incoming orders, not just the bot placing the quotes.
Source: https://docs.cdp.coinbase.com/exchange/concepts/matching-engine
Coinbase's existing self-trade prevention rules apply when that user's orders cross. The newer order's prevention setting takes precedence. For two limit orders, the default cancels the smaller order and reduces the larger by the same size. Equal-sized orders are both cancelled.
That matters if one bot is maintaining quotes while another sends a limit order priced to trade immediately. The incoming order can remove or shrink a resting quote rather than fill against it.
Before running those strategies together, choose which order should survive that collision. Coinbase offers settings to cancel the oldest order, the newest order, or both. “Cancel newest” preserves the resting order; “cancel oldest” removes it and lets the newer order continue trying to execute. Check the setting on the incoming orders, not just the bot placing the quotes.
Source: https://docs.cdp.coinbase.com/exchange/concepts/matching-engine