Any token on the Uniswap Labs Default Tokens List is eligible to be routed using UniswapX.
There may be instances when an UniswapX eligible token is unavailable to be swapped through UniswapX.
This is because the swap availability of eligible tokens on UniswapX is subject to change based on if the filler market is able to execute to swap competitively.
If the filler market cannot execute swaps competitively for an eligible token then the swap will then be completed using the liquidity pools on Uniswap v2 and v3.
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