Add diagnosis code to negotiated price object

schemas/in-network-rates/README.md

@@ -103,6 +103,7 @@ The negotiated price object contains negotiated pricing information that the typ
 | **service_code** | Place of Service Code | An array of two-digit strings | The [CMS-maintained two-digit code](https://www.cms.gov/Medicare/Coding/place-of-service-codes/Place_of_Service_Code_Set) that is placed on a professional claim to indicate the setting in which a service was provided. When attribute of `billing_class` has the value of "professional", `service_code` is required.  | No |
 | **billing_class** | Billing Class | String | Allowed values: "professional", "institutional", "both" | Yes |
 | **billing_code_modifier** | Billing Code Modifier | Array | An array of strings. There are certain billing code types that allow for modifiers (e.g. The CPT coding type allows for modifiers). If a negotiated rate for a billing code type is dependent on a modifier for the reported item or service, then an additional negotiated price object should be included to represent the difference. | No |
+| **diagnosis_code** | Diagnosis Code | Array | An array of strings. The [NCHS-maintained ICD-10 code](https://www.cdc.gov/nchs/icd/icd-10-cm/index.html) that is placed on a claim to indicate the patient diagnosis. This can be supplied to differentiate rates based on diagnosis for the same service code.| No |
 | **additional_information** | Additional Information | String | The additional information text field can be used to provide context for negotiated arrangements that do not fit the existing schema format. Please open a Github discussion to ask a question about your situation if you plan to use this attribute. | No |
 
 ##### Additional Notes

schemas/in-network-rates/in-network-rates.json

@@ -410,6 +410,14 @@
           "uniqueItems": true,
           "default": []
         },
+        "diagnosis_code": {
+          "type": "array",
+          "items": {
+            "type": "string"
+          },
+          "uniqueItems": true,
+          "default": []
+        },
         "negotiated_rate": {
           "type": "number"
         },