While CVX has kept up with worldwide COVID-19 vaccines, it's not guaranteed to have codes for vaccines not authorized for use in the US. To balance the need for support of vaccines worldwide with limiting the number of code systems implementers need to support, we propose limiting vaccineCode to the following:  Any CVX Children of SNOMED#787859002 "Vaccine product" – this includes codes from any SNOMED edition that are children of this concept Children of the following ICD-11 codes: XM3KV2 Bacterial vaccines; XM61M7 Viral vaccines; or XM7C66 Bacterial and viral vaccines, combined Additionally, we propose allowing only a single value for vaccineCode that is from the ValueSet described above. The concern with allowing arbitrary vaccineCode values like we currently do is that wallet apps likely won't be able to display anything beyond CVX/SNOMED/ICD-11 in a human-friendly way (an important principle of SHCs is that all the included information should be human-readable), and general purpose Verifiers would likely not be able to process arbitrary values. While these changes reduce the theoretical flexibility of SMART Health Cards for vaccines from the ballot version of the IG, we don't believe this poses a practical problem for current or future use cases.