“Some of the best things on the web are free,” muses Lance Uggla, CEO of Markit Group. “When I look at how financial markets will use technology to transform their networks of participants, I think the word ‘free’ has to be included.”

He is referring to the way Facebook and Google are free — and to the new commercial models they have spawned. The financial services industry is poised for its own Google-like revolution, says Uggla, who in ten years has built Markit into a global force in market information and transaction-processing services. No. 5 in this year’s Tech 50, Institutional Investor’s annual ranking of financial technology leaders and innovators, Uggla says he spends 10 to 15 percent of his time “thinking and talking with others about a free strategy and how disruptive it would be to today’s business model.”

See the full ranking, with profiles, here.

For last year's Tech 40, click here.

“Disruptive” is the operative word, and it is a thread running through the Tech 50. The idea harks back to The Innovator’s Dilemma, a 1997 book by Harvard Business School professor Clayton Christensen that explained how long-entrenched, industry-leading companies can fail to anticipate “disruptive technologies” or seize the opportunities they present.

Today’s financial services disrupters do not so much fear falling into obsolescence like Christensen’s 20th-century case studies — such as Digital Equipment Corp., which was blindsided by the personal computer — as they are eager to make innovative leaps to gain competitive advantages. Taking the productivity and efficiency afforded by automation as a given, executives see technology in a more opportunistic light: as a tool for growth.

Disruption defines why Reto Francioni and Duncan Niederauer, the respective CEOs of  Deutsche Börse and NYSE Euronext, jointly rank No. 1 on the Tech 50. Their agreement in February to merge and create the world’s biggest exchange organization was itself a disruptive, even provocative, strategic stroke. Now they face the further test of making their deal pay off in ways that few large-scale mergers do.

It falls to an executive team of seasoned technologists — including, besides Francioni and Niederauer, Deutsche Börse derivatives chief Andreas Preuss and NYSE president (and IBM Corp. veteran) Dominique Cerutti — not only to accomplish the essential systems integrations but also to develop and deploy disruptive, business-transforming, revenue-­enhancing technology services as their company becomes bigger and more complex.