If you suspect a hub is leaking, see below what you can do.

Problem

Upon inspection, you detect one of the following:

You find a small film of oil on a freshly delivered hub.
You find oil fluid on the left side of the hub, the side with the freewheel.
You find oil fluid on the right side of the hub, the side with the brake adapter.
You find a leak from a cover location of the hub.

Note that our hubs are ⅓ filled with a special oil.

Solution

For a new hub that has just been delivered:

Wipe it clean and monitor for future leaks. This is likely just leftover fluid from the assembly process.

For a used hub that is leaking from the left-axle side (freewheel), the right-axle side (brake), or the hub cover:

Wipe the hub clean and monitor for leakages.
If the problem persists and the hub is within 2 years of age, return the hub using the warranty request form. Enviolo hubs are closed containers and need to be sent back for closer inspection.

You should now have a clean hub or otherwise have it sent to Enviolo Support for closer inspection.