This code system http://terminology.hl7.org/CodeSystem/ex-coverage-financial-exception defines the following codes:

CodeDisplayDefinition
retired RetiredRetired persons have all copays and deductibles reduced.
foster Foster childChildren in the foster care have all copays and deductibles waived.
<status value="draft"/><publisher value="Financial Management"/><contact><telecom><system value="url"/><value value="http://hl7.org/fhir"/></telecom></contact><description value="This codeset includes Example Coverage Financial Exceptions Code."/><copyright value="HL7 Inc."/><caseSensitive value="true"/><content value="complete"/><concept><code value="retired"/><display value="Retired"/><definition value="Retired persons have all copays and deductibles reduced."/></concept><concept><code value="foster"/><display value="Foster child"/><definition value="Children in the foster care have all copays and deductibles waived."/></concept></CodeSystem>