Part 1. Changes to Factory Structure (Singleton Contract) UniswapV2 and V3 operate by creating numerous child contracts (Pairs) through a primary contract (Factory). The Factory records minimal information about the Pairs, does not engage in internal swap transactions, and does not hold any tokens. In V2, the Factory holds basic information, such as the addresses of Pairs and the tokens involved in each Pair. In V3, the Factory keeps slightly more complex information, such as the Pair's ...