| Name | Type | Description | Notes |
|---|---|---|---|
| startDate | \DateTime | Timestamp at which point the referral code becomes valid. | [optional] |
| expiryDate | \DateTime | Expiration date of the referral code. Referral never expires if this is omitted. | [optional] |
| usageLimit | int | The number of times a referral code can be used. `0` means no limit but any campaign usage limits will still apply. | [optional] |