Bangalore-based neobank Open is in advanced stages of talks to raise about $100 million, according to two sources familiar with the matter. Temasek, the Singaporean government’s sovereign wealth fund, and General Atlantic are positioning to co-lead the Series C financing round, which values the Indian startup at pre-money $600 million, the sources told TechCrunch, requesting anonymity as the matter is private. Open was valued at about $150 million in its Series B funding round two years ago. Existing investor Tiger Global, PayPal, which shuttered its domestic operations in the world’s…