Punjab National Bank Scam
The Punjab National Bank scam refers to the fraudulent letter of undertaking (LoU) scam worth ₹14,357 crore (approximately US$2 billion in 2018). The LoUs were issued by Punjab National Bank (PNB) at its branch in Fort, Mumbai, making the bank liable for the amount.
Source: Wikipedia — Punjab National Bank Scam (CC BY-SA 4.0)