Dust amount - minimum amount a bitcoin transaction output is allowed through current policy. Since ark has unilateral exit, we currently enforce it. Although you can always go to a miner out of band and get it included in a block but thats more of a cheat code than pragmatic.
However we know that at that amount, perhaps it's not enforceability that matters, but rather the claim, and collecting a sum of claims higher than dust should allow you to go to enforceability again. Work in progress and just the rationale right now, but it's in our considerations