Generally speaking, any creditors of a decedent at the time of his death can file a claim against the decedent's estate. The executor of the estate has a duty to pay any creditors that make a legitimate claim against the estate before distributing assets to the decedent's heirs. The process the estate goes through probate and how creditors are allowed to file claims is governed by state law.
This form is a settlement of certain claims against the estate.