My dependant has a 1095A as he's covered on it with my ex. My ex is claiming the 1095A. I don't want to claim it also. It's asking me, my son and my ex to claim it

[NicolleR1]

If you are claiming your dependent on your return but he is listed on another policy and was issued a 1095-A, you will need to claim the portion that belongs to him in your return. You can also agree with the other person (the other parent) who will be claiming the portion of your dependent. 

You will still need to enter Form 1095-A in your return. If the other parent is claiming the full policy, you will then enter all the information as listed on the form, then check that the policy is shared with someone else, and allocate 0% of the policy on your return. 

See the following response to a previous thread by @DawnC

https://ttlc.intuit.com/community/tax-credits-deductions/discussion/1095-allocation/00/3150171#:~:te...