This field includes a validation script that ensures that the value provided by a user is in the proper Vehicle Identification Number (VIN) format. Specifically, the script ensures that the value is 17 characters long does not contain these characters: o, O, i, I, u, or U.
Within the context of the sample application, this requirement is defined in "BPR10: Enforce VIN Number Accuracy" in the Developer Guide and the implementation is described in "Data Quality Design" in the Developer Guide.
See Adding a Validation Script to a Field for a detailed example using this script.