Twitter, American microblogging and social networking service, completed the investment in Aleph Group, a global enabler of digital advertising. Financial terms were not disclosed. "Aleph has been a valuable and strategic partner to Twitter for many years. With a diverse set of capabilities, Aleph has supported our business globally, both as a sales and technology partner. This investment is a natural evolution in our relationship with Aleph," Sarah Personette, Twitter Chief Customer Officer.