For tax purposes, there is no such thing as joint or shared custody, regardless of what your legal agreement says. The requirement, to be custodial parent, is that the child live with you MORE than 50% of the time. One of you has to be the custodial parent and the other the non-custodial parent.
Yes, your first two paragraphs are correct.
It would be best if the custodial parent paid the bulk of the child care expense for the year. But, there is a recent tax court ruling that seems to say that you can take the deduction even if he was the one that actually paid it under the theory that his paying the expense is just another form of child support and it was your money that paid for it. The maximum amount of child care that can be claimed for one child is $3000 ($6,000 for 2 or more children). But, in order to claim the maximum amount, you must have at least that much earned income (usually not a problem).
