Major Wall Street banks like Goldman Sachs and JPMorgan have invested almost $300 million in Symphony, a startup building encrypted, cloud-based communication tools.  Google is also an investor.

The banks want to build a platform they can all communicate on to help them cut down on expensive Bloomberg terminals.

Almost four years into the project, Symphony has over 300,000 users.

But there are questions around usage, partnerships, and whether it’s really having an effect on Bloomberg.

This story, based on conversations with 35 sources, looks at how Wall Street’s audacious bet has gone so far and the challenges the startup still faces.

“Thank you David Gurle,” French President Emmanuel Macron tweeted in June.  “Your trust and your enthusiasm show, once again, that France is back.”

Macron, one of the most powerful men in European politics, was praising Gurle’s decision to set up a new French research and development center for his company Symphony, a secure messaging platform.

For those who know Gurle, the French president’s praise will not have been a surprise.  The son of two former diplomats and a veteran Silicon Valley executive for almost two decades, Gurle is known as the consummate salesman who could “charm the birds from the trees,” according to a former employee.

This charm has come in handy.  Banks, asset managers, and even Google have invested almost $300 million into Symphony, a secure, cloud-based chat platform conceived as a hub for any and all financial work.  Banks hope Symphony can engineer a …