Bharat Masrani has spent a decade as the Canadian bank's top executive and is pushing 70. But as the bank undergoes a U.S. Justice Department probe, it's unclear when he'll step down or who's next in line.

The lawmakers, led by Sen. Elizabeth Warren, D-Mass., said the deal would further anti-consumer bank consolidation, but also criticized the OCC's proposed changes to the merger process, asking that they be strengthened.

BMO Financial Group doubled its mainframe capacity, prepared a cloud staging platform and used chaos engineering to ensure its Bank of the West integration went smoothly.

The two companies in the largest bank merger since the 2008 financial crisis released details of their agreement. It leaves the door open for Discover to field better offers, though the payments company would pay a break-up fee of 4% if it accepts one.

In the wake of the largest U.S. bank deal in more than 15 years, industry executives offered mixed views about the prospects for more big acquisitions. They also spoke about the deal's impact on competition in the credit card business.

The credit card lender's blockbuster acquisition of Discover is not guaranteed to get across the finish line. But co-founder and CEO Richard Fairbank appears to see the rewards that would come from controlling a payments network as outweighing the potential downside.

Some analysts said that the Capital One-Discover deal would undercut the reasoning behind the Credit Card Competition Act — authored by Sen. Dick Durbin, D-Ill. — which aims to spur competition for Visa and Mastercard.

In implementing Section 1033, the Consumer Financial Protection Bureau is leaving out auto loans, one of the largest sources of consumer debt.

The combined company could streamline card payments in a manner similar to American Express' "three party network" — while also doing more with artificial intelligence and other technologies.

The blockbuster merger proposal will be reviewed at a time when the Biden administration is expressing skepticism about consolidation. Its analysis will have to account for markets dominated by both big banks and the likes of Visa and Mastercard.