These wines are from producers who have certification for Organic or Biodynamic farming in their vineyards.
Under US regulations this is not the same as Organic Wine, which is typically made without any sulfite additions at all.
An Organic Wine must have only trace amounts of "free SO2" produced naturally by the fermentation itself.
"Free" in this context simply means sulphur dioxide that is still available in the wine to bind with those
stealthy oxygen atoms waiting to cause spoilage, thus performing its desired protective role.
Got that? I hope so, because my head hurts just from writing it. ;>) Peter G