As always, information about B12 in any product may be misleading because detailed information about how this product influences our levels of B12 etc. in human blood normally isn't included in these reports... but here we go:

However, 91.43 ?g/100 gdw was produced by Klebsiella sp.KB2 after 36 h which is equivalent to about 0.32?g per gram wet weigh and sufficient
for the daily requirement of 1 ?g (Herbert, 1984) if are eats 3-4 g of Thua-
nao per wet weight.

Thua-nao as sold in market places often has an unpleasant smell
and, when heated give a strong and persistent smell of ammonia. This smell could not be noticed when soybeans fermented with either monoculture of Bacillus sp. B4 or a mixed cultures of Bacillus sp. B4 and Klebsiella sp.KB2.

(Thua nao is a natto-like fermented soy product from Thailand.)

Here's another link:
The soybeans soaked in water are cooked in low heat for 3-4 hours until the beans are soft and the water is drained. The beans are placed on a layer of banana leaf on a bamboo tray and covered with banana leaves. The beans are allowed to ferment naturally for 3-4 days until the beans are covered with a sticky, viscous and colorless gum. Small quantity of paste is used to make small ball of one to one and half inches diameter and they are processed to form thin chips, sun dried and marketed. Through research, it was found that use of mixed culture fermentation of oligosaccharides, utilizing Bacillus subtilis and vitamin B12 producing Bacillus megaterium, has improved the quality of thua-nao. Soybean oligosaccharide sugar utilizing Bacillus was isolated from various sources of thua-nao. Bacillus subtilis B4 was found to produce the best proteolytic activity, as well as soybean sugar-utilizing property, among 120 Bacillus isolates. Mixed fermentation of Bacillus B4 and Bacillus megaterium under optimum conditions, could improve the quality of thua-nao by enhancing more digestible soybean proteins, soybean sugar, as well as vitamin B12 content in the fermented masses (Yongsmith, 1999). Factors affecting the fermentation are currently examined to produce a more sanitary and uniform product.

Thua-nao is considered as an inexpensive high-protein food that could be easily produced, and if properly prepared has a long shelf life. Thua-nao paste and chips contain 16.9 percent and 36.8 percent of protein and 7.4 percent and 14.8 percent fat, respectively. Due to high vitamin B12 thua-nao products have become popular among vegetarian population.