Since the YTCA is the owner/keeper of the standard I'll post this way too.
Yorkshire Terrier Club of America
One must keep in mind the standard is written for those of us who breed/exhibit as a guideline. It is what we should be striving for.
For the OP who is looking for a tiny, and requesting a reputable teacup breeder....well it is an oxymoron.....What I do suggest if this is what your heart is set on, is go to the YTCA.org breeder referral page....My reasoning is this.....to be pretty assurred that you will get what you want.......Many exhibitor/breeders hold on to dogs that have all the qualities that we are looking for in a show dog, but size......we hold on to them in hopes that they will grow and they don't.....so, we'll place them. These pups can be anywhere from 6 months to a year......gorgeous pups in full coat or near that....that just didn't grow. What is great about this, is that they are pretty much trained.