We recommend the following best practices for shared links in Box:

1. For how to create a shared link, please see this article from Box
2. Unless there is a strong need to customize the link, use the default Box shared link. They are more secure.
3. Regardless of whether it is a default or custom shared link, if you’re sharing any data that shouldn’t be public and need to set the access level to “people with the link,” set a password on your link.
4. When you create a shared link of any kind, take the time to think about how long the link will be necessary. If you can determine a time limit, set an expiration date. Expiration dates will save you time and worry later.

Beginning in mid-March 2019, Box requires that all custom links be at least 12 characters in length.