-Favor “proof of” vs. “actual data”. Example: overAge: 21 vs. birthdate. +
+In order to enable recipients of verifiable claims to use them in a variety of circumstances without revealing more personally identifiable information than necessary for the transaction, issuers should consider limiting the information published in a claim to a minimal set needed for the expected purposes. +One way to avoid placing personally identifiable information in a claim is to use an "abstract" property that meets the needs of inspectors without providing specific information about the subject. +
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+An example in this document is the use of the ageOver property as opposed to a specific birthdate that would constitute much stronger personally identifiable information.
+If retailers in a market commonly require purchasers to be older than a specific age, an issuer trusted in that market may choose to offer a credential claiming that subjects have met that requirement as opposed to offering claims of their specific birthdates.
+This enables individual customers to purchase items without revealing specific personally identifiable information.