So transferring oils from one vial to another, assuming both are sealed and sterile, and a sterile process is used, should not affect long term storage shelf life? My concern is the same as the post you were replying to here, that by piercing the stopper, it somehow starts some countdown timer. I imagine this belief assumes sterility is compromised by this by either the introduction of bacteria or by a compromised stopper seal? I plan to use a thinner gauge needle to insure that the stopper reseals itself fully, so instead of an 18g maybe a 23g. Would a filter be necessary, or only needed if there is some assumed contaminant already present?