So you didn't use a barrier product on your pure aniline leather, and you haven't kept up on the maintenance (or didn't know you were supposed to)? You now have a head oil stain on the leather - such as this one from one of my customers who bought this from my store in 2012. Some people have chemicals in their bodies that soak through into leathers, often it can be folks on a lot of medications. Not everyone experiences this happening and there is no way to tell if you might have an issue with yours ahead of time. This customer called to request a new back casing be made, however the leather had been retired so that was not possible. I sent this photo of to Pamela at Leather Solutions International to see if she would be able to fix it.

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Her reply:

"Yes the bid oils can be removed as long as we can get inside the cushion. It make take a week to get it all out. We spray a degreaser on the backside which pulls the oils through as it removes it from the back. There is rarely any color work that needs to be done on the surface. We recommend cleaning and protecting every three months to remove the body oils on the surface before it has time to penetrate and absorb into the leather. Send me the casing and I will remove the oils."

Leather Solutions Int'l
PO Box 2014
Asheboro, NC. 27204

Obviously an ounce of prevention is worth a pound of cure, so I would encourage folks to use the preventive products so you don't have to go through all this. I have pure anilines in my own home that are close to 30 years in use, no staining, no marking....but I do take care of the hides with the Leather Solutions products, and that's the key to avoiding issues.