X12 implementation guides occasionally establish specific criteria for using the K3 segment to meet an unexpected data requirement on a short-term basis. Since the K3 segment’s usage is atypical, X12 provides this quick reference list of RFIs related to use of the K3 segment for the convenience of implementers, trading partners, and regulators.
| RFI | Title | Supported? |
| 2439 | Service Window on 837D | No |
| 2387 | AUC Mandate | Yes for 005010 |
| 2287 | BPR-02 vs. Actual Deposit Amt | Yes for 005010 |
| 2214 | NY NoFault Remit Data | No |
| 2213 | NY NoFault Data | No |
| 1938 | 2300 K3 for Ambulance Data | No |
| 1886 | 837P - Report repackaged NDC | Yes for 005010 |
| 1740 | 5010 K3 Usage | No |
| 1595 | K3 Usage for Health Safety Net Claims | Yes, version not mentioned but implies 005010 |
| 1065 | Tooth information for 837P | No |
| 1399 | Jurisdictional state 5010 | Yes for 004010, explicitly no for 005010 |
| 913 | 837D 5010 Request for K3 Use | Yes for 005010 |