Merrill Lynch still sort of exists, in the sense that people will still say they work there. They have officially rebranded to "Bank of America Merrill Lynch", but I imagine people that were originally hired by ML will still say they work for ML and keep their LinkedIn profiles updated accordingly. (I'm on the other side, and I tell people I work for the Bank of America rather than "Bank of America Merrill Lynch", because that's a mouthful, and frankly, not a very creative name.)