mumbai/Bengaluru, Jan. 24 -- News of the US market regulator seeking to send summons in a bribery case directly to Adani Group promoter Gautam Adani and his nephew Sagar sent the group's listed stocks tumbling between 3% and 15% Friday. Mint calculations show the stocks cumulatively lost nearly a tenth of their value, or a market capitalisation loss of over Rs.1.1 trillion.P19...