Volks has been the top Japanese brand for many years, but some smaller brands have come and gone as well. There aren't many of them compared to the number of Korean and Chinese companies, possibly due to Volks' monopoly of the market.
Gentaro Araki started out sculpting spicy garage kits and dipped his toes in dolls in a collaboration with Volks for U-Noss. As far as I know, this is the only human who has managed to collab with Volks way back in 2000. I can't tell who has the rights to U-Noss anymore because Volks will not do replacement services and Araki does not sell them. Araki doesn't seem to have or have rights to the mold and I seem to remember Volks refusing to do replacements for U-Noss. It was a very cool collaboration that will never happen again.
In 2003, he started selling his own dolls under the name Alchemic Labo.
Allegedly, Unola was originally sold at Dolpa 12 (source). Are these allowed at Volks events or stores?
Araki also sold the rights to U-noa Zero to Hobby Japan.
They sell 1/3 girls. Once sold 1/4 girls, including kits, and male heads. Once sold by auction, mail order, and events.
Kame and Codi's Kiki is the epitome of kawaii. Since Kiki, they have released a few more stylized tinies.
These dolls were once incredibly hard to get. Only fullset models were originally made, and not many either. KJ was notorious for keeping their dolls out of foreigners hands. Proxy auction wins would be canceled and they refused to sell them to foreigners to events. You'd be lucky to only spend $1000 USD to get one.
Despite all their efforts, Kiki was recasted.
A few years later, KJ partnered with AZONE to create a ABS version of Kiki. The first Kikipop was released in September 2015. A few years after this, KJ opened an Etsy store and now ships worldwide with no hassle.
KJ is a bit of an oddity in that they almost only sell doll in stock. For some new releases, there have been preorders.
Heads only. Came back after a hiatus for 3D printing dolls in 2014 and completely disappeared soon after.