How Does the Aggregation of Order Books across Multiple Exchanges Affect Perceived Depth?

Order book aggregation combines the liquidity from several different exchanges into a single, consolidated view. This provides a much deeper, more accurate perception of the total market liquidity for an asset.

While it doesn't create new liquidity, it makes the existing depth across venues more visible, which can encourage larger trades and potentially contribute to tighter effective spreads by routing to the best price.