What is this oil? (wet lube)
I think you probably have Shimano's wet lube.  Confidence could increase if you feel that the point of sale was a reputable store with legitimate distributorship.   Speaking of all that, are you a believer that Amazon represents a company like that?   Here's an Amazon post in which the label appears very similar and the manufacturers reference number begins "WS..." 

While this rationale is fairly weak counterfeiting a relatively inexpensive product isn't cost effective, legalities aside.  As they say, "the proof is in the pudding," so I would try it out and see how it works out.