One of the affiliates (Shengzhan) owns valuable data about user activity. The other (Shengjiang) runs a network that sells 2M+ real/virtual prepaid gaming cards via 180K distribution channels.
Shanda claims service fees paid to the affiliates made up 21.3% of its Q1 revenue, and that buying the companies will help it deliver the kind of integrated platform it considers crucial for mobile success.
Shanda is paying for the deals with cash, deferred payments, and the settlement of an outstanding loan receivable.
Shares had more than doubled since early May before today's plunge.
Fellow online game providers NetEase (NTES -2.6%), Qihoo (QIHU -4.1%), Perfect World (PWRD -5.3%), and Giant Interactive (GA -5%) are selling off. Sohu and subsidiary Changyou's disappointing Q2 results and Q3 guidance are the main trigger, though a moderate selloff in Shanghai isn't helping either.