The best way to remove blue jean stains from leather seats is to use a product called Megulars Leather Cleaner and Conditioner. Rub in the cleaner with your hands and fingers as if you were massaging the seats. The stain will gradually begin to dissolve. Leave it for a few minutes and then wipe the excess off gently with a soft, clean cloth. Make sure the cloth is dry. This process will require some patience as it could take some time. One thing to bear in mind that many modern cars have a plastic coating on the top of the actual leather seats, so the plastic is actually what is stained, as it reacts with certain types of dye, especially those in jeans. There are a couple of other products available for tougher stains called Tanners Preserve Leather Cleaner and Tanners Preserve Leather Conditioner. These should be applied in exactly the same way as the Megulars cleaner. Use the shampoo first, massaging in with the fingers and then wipe dry with a clean cloth, and then apply the conditioner repeating the process. Another product that can help to get the stains out of leather is called Woolite. Mix one part of Woolite with six parts of water and use a soft bristled brush, brushing softly so as to not mark or tear the leather. You can then apply a protector to the plastic coating. Aerospace 303 is a good example of this and will keep the surfaces free from grease and dirt. If there is no plastic coating on the seats then you may be best just using water and vinegar, as the acidic qualities in the vinegar will break down the stain. It will also need a little patience though. Coke can also work in this way although it could stain itself.
Blue Jean Stains are not very easy to remove specially from Leather Seats from your car.You can try first using the pencil eraser on the fabric and then using white vinegar to wipe them clean.
Use a magic eraser!!! They work magic just like they say!!!and the best part is that all you have to use is that and water!
I've just had the same problem and just submitted this same question on the Good Housekeeping website. Yesterday, I took the jeans back to Macy's and they refunded my money so you may want to return yours also. These jeans were Ralph Lauren and this shouldn't have happened. They even rubbed off on my hand. I have washed them at least 6 or 7 times.
Coke. It has acidic properties that breakdown pretty much anything.
3M Easy Erasing Pad.