In a blockbuster $27 billion deal that's certain to threaten Bloomberg's financial-data empire, the London Stock Exchange struck an agreement this week to buy the data company Refinitiv. The tie-up highlights trading venues' desire to move beyond low-margin trading and clearing into the more lucrative business of selling data. LSE CEO David Schwimmer, who joined the stock-exchange group less than a year ago from Goldman Sachs, is driving the industry-changing transaction. Our banking reporter Dakin Campbell talked to Schwimmer's former colleagues and clients, who told him why Schwimmer is ideally placed to do the deal. If you aren't yet a subscriber to Wall Street Insider, you can sign up here.