Goldman Sachs, China and Theranos: WHAT YOU NEED TO KNOW ON WALL STREET

Finance Insider is Business Insider's summary of the top stories of the past 24 hours.

What do your clients think of you?

It seems like a pretty fundamental question for anyone in a service industry. In bond trading, however, it has been a mystery until recently.

And that means Wall Street banks are only now figuring out the answer to this incredibly important question.

Elsewhere on Wall Street, Ben Melkman, a partner at hedge fund Brevan Howard, is planning to launch his own fund after winning big on Argentina.

Google has passed Goldman Sachs in one measure of prestige. And here's how Goldman Sachs' client list has changed.

Investment bankers at UBS can now take at least two hours of "personal time" a week in the latest attempt by a bank to retain staff with a better work-life balance.

China could be about to plunge us all into a world of pain, the world's economic 'canary in the coal mine' flopped again, and several automakers are reporting huge drops in May sales.

Salesforce is buying Demandware in a $2.8 billion deal. Jose Cuervo is planning a $1 billion IPO. And SoftBank is planning to sell $7.9 billion in Alibaba stock to cut debt.

Theranos CEO Elizabeth Holmes' net worth is now zero, according to Forbes.

And lastly, safe sales are skyrocketing because of negative interest rates.

Here are the top Wall Street headlines at midday:

A former chair of the FDIC has become the first board member of an ex-Goldman banker's 401(k) startup ? Bair is joining startup blooom as its first advisory board member.

Don't count on this oil 'wild card' coming back anytime soon ? Libya has been the big supply "wild card" this year.

Hackers are bombarding the Fed, and have broken in 50 times over the last 4 years ? The US Federal Reserve detected more than 50 cyber breaches between 2011 and 2015, with several incidents described internally as "espionage," according to Fed records.

Faraday Future just got the green light on what could be its 2nd factory ? Faraday Future and the city of Vallejo, California, have entered an agreement that could place the electric-car startup's second factory in the San Francisco Bay Area suburb.

7 things every guy needs before heading to the beach ? Beach season has begun. Are you ready?