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# preferredAIDList

The preferred Application Identifier (AID) or Registered Application Provider Identifier (RID).

```
var preferredAIDList: [Data]
```

## Discussion

An ordered list of valid binary data between 5 and 16 bytes representing the preferred AID or RID.
Use the preferred AID or RID when completing transactions with co-badged cards - a *co-badged*
or *co-branded* card is a payment card that supports two or more payment brands.

> Note: In iOS 16 and earlier, the framework only uses the first entry. In iOS 17 and later, the list can have up to four entries.

---

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