What you need to know on Wall Street today

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Seth Golden, a former Target manager, rose to fame in financial circles following reports that he'd made millions shorting volatility.

When the stock market went haywire in early February, sending the Cboe Volatility Index surging, many Business Insider readers wondered how Golden had fared.

He wants to let everyone know that he emerged from the market blowup largely unscathed, and he has provided an explanation of how that's possible. Here's our story .

Elsewhere in trading news, $35 billion hedge fund Millennium Management has hired a top trader from Citigroup .

In deal news, Cigna is buying Express Scripts in a $67 billion deal. Express Scripts is one of the three massive PBMs that help negotiate lower prices for prescription drugs in the form of rebates on behalf of health plans . It was the only major PBM to stand on its own, and its stock has been weathering news that Amazon is interested in getting into healthcare.

The deal shows how the healthcare business is being redrawn . The banks that worked on the deal are expected to earn as much as $200 million.

In other deal news, here's the story behind S&P Global's $550 million deal to buy hot Wall Street AI startup Kensho .

Lastly, in trade news:

• There's chaos around the White House over Trump's big tariff announcement
• TRUMP: Gary Cohn 'may be a globalist, but I still like him,' and I suspect he may come back to the White House
• The Trump administration is pulling the economy in 2 directions and creating problems for the Fed
• Wall Street is loving US Steel as it gears up for Trump's tariffs