The writer initially owns the rights...composer in the case of music, writer in the case of lyrics. From there it is up to them to sell the rights to others. It is a simple copyright question. FYI, to prove copyright easily mail the item registered mail in a sealed envelope to yourself. The date of the mailing can be the proof of when the item was created.

Once the gas has been transferred into the stations pumps you can also see a difference sometimes if the equipment is badly maintained. Water or other things can seep into the gas and wind up in your tank.