SoftBank CEO Masayoshi Son

Sprint and T-Mobile shares fell Monday, on a Japanese media report that SoftBank is prepared to pull the plug on a proposed merger between the two carriers. Per the Nikkei news service:

"SoftBank Group plans to break off negotiations on a merger between subsidiary Sprint and T-Mobile US amid a failure to agree on ownership of the combined entity."

Why it matters: Combining Sprint and T-Mobile would radically transform the U.S. wireless market, creating a more formidable adversary for Verizon and AT&T but reducing the number of overall competitors.

Surprise, surprise: Earlier reports had suggested that the merger was gaining momentum, so this is a shock to the M&A system. Particularly the notion of the bullet being fired by Sprint owner SoftBank, as there was a sense that CEO Masayoshi Son had been publicly supportive of President Trump in order to better the deal's chances of regulatory approval.

Caveat: Don't underestimate Son or the possibility that SoftBank "walking away" is a negotiating tactic. Axios has reached out to a SoftBank spokesperson, and will update this post if we receive comment.

Go deeper: How a Sprint, T-Mobile merger could jolt wireless

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Downtown Chicago hit by widespread looting

Police officers inspect a damaged Best Buy in Chicago that was looted and vandalized. Photo: Scott Olson/Getty Images

Chicago police responded to hundreds of people looting stores and causing widespread property damage in the city's downtown overnight, resulting in at least one exchange of gunfire, the Chicago Tribune reports.

The state of play: Police superintendent David Brown said the event was a coordinated response after an officer shot a suspect on Sunday evening, per CBS Chicago.

McDonald's sues former CEO, alleging he lied about relationships with employees

Former McDonald's CEO Steve Easterbrook. Photo: Drew Angerer/Getty Images

McDonald's on Monday sued its former CEO Steve Easterbrook, seeking to recoup tens of millions in severance benefits while alleging he took part in and concealed undisclosed relationships with company employees, per the New York Times.

Why it matters: Corporations have traditionally chosen to ignore executive misbehavior to avoid bad press, but they have become more proactive — especially with the rise of the #MeToo and Black Lives Matter movements — in addressing issues head-on.

The transformation of the Fed

Illustration: Eniola Odetunde/Axios

The Federal Reserve is undergoing an overhaul. Conceived to keep inflation in check and oversee the country's money supply, the central bank is now essentially directing the economy and moving away from worries about rising prices.

What we're hearing: The move to act less quickly and forcefully to tamp down on inflation has been in the works for years, but some economists fear that the Fed is moving too far from its original mandate.