Google Play License Service: UserId Field Claims?

According to its reference implementation, we have to assume that the Google Play Licensing Serv {ice, er} in userId , returns // Application user id ... a> On the other hand, the LVL link makes no such obligation.

In practice, the return value is represented as long binary data, perhaps even starting at (at least) a 0x00

Base64 encoded byte .

From the comment, it should be assumed that this field value is a client id, confusing but still unique for each application , so that the client can be identified using this value, whereas the other hand is not suitable for figuring out if that was same client as in another app that is potentially published.

However, if anyone relied on this assumption for business, it must be officially confirmed , and I cannot find such confirmation. Also, a maximum length statement would be quite helpful, but I haven't found it yet.

Has anyone found more information on this or would like to share their experiences? I would really appreciate it.

Update: . Can anyone confirm that these IDs are 24 x 8 bits padded binary data padded with (25) byte 0x00

?