Y Collection or YSL? Full Ankle Length Silk Skirt

Hi!
I just bought a lovely baby blue silk skirt on ebay from a seller who several times described it as vintage Yves Saint Laurent. Upon receiving the skirt however, the label is completely unfamiliar to me. I don't believe the seller was trying to pull one over since I paid only $15 and I love the skirt either way, but I would like to know the truth behind the label.
Can anyone help me identify this label?
Thank you!

 

Is there an RN number on the back of the label or perhaps on the other label?