Bill Ackman, Atlantic City and Goldman Sachs

Manuel Balce Ceneta/AP

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Activist investor Bill Ackman says “of course” he regrets investing in Valeant.

“There’s been a lot of brain damage in the last five weeks working with the board,” he said in an interview with CNBC.

Atlantic City just averted a massive disaster, and three banks just lost close to $100 million from the collapse of another megadeal.

Goldman Sachs is going down-market, and everyone is looking at Goldman’s fixed income business when they should be looking at the equities unit.

Morgan Stanley questioned the dominance of Bloomberg, and the response shows just how entrenched it is.

Business Insider is reporting from the Milken Institute conference. Economist Mohammed El-Erian painted a pretty depressing picture of the global economy on one panel early Monday.

The same panel agreed that there’s a word for people who don’t know how to invest in emerging markets: “tourists.” Check back here for more coverage through the rest of the day.

Lastly, Berkshire Hathaway’s annual meeting took place over the weekend. Here’s what you missed, and here is Myles Udland on what the meeting is really about.

Here are the top Wall Street headlines at midday:

Craig Wright claims he created Bitcoin – The Australian IT executive who late last year was engulfed by rumors that he invented Bitcoin has claimed he really is behind the digital currency.

Forget millennials — these 2 groups are the real future of America’s consumers – Everyone keeps talking about millennials and their shopping habits.

The biggest names in finance all want the government to do one thing, but it’s not going to happen – It can be hard for people on Wall Street to agree on anything.

Tesla put a Model X in a giant plastic bubble to test Bioweapon Defense Mode – Tesla’s Bioweapon Defense Mode is one of the company’s most talked about, but least understood features.

China is carrying $1 trillion in bad debt – The amount of debt being carried in the Chinese economy — mostly by state-owned “zombie” companies — is now so high that it could lead to a financial crisis.

Meet the billionaires of 740 Park Avenue, one of New York’s historic ‘Towers of Power’ – On a quiet, tree-lined block on the Upper East Side, 740 Park Avenue rises up: a legendary address, at one time considered (and, perhaps, still) the most important residential building in New York City.