At the start of trading, JPMorgan Chase (NYSE:JPM) is already up by 1.58% after being up in overnight trading, as well. After a week of bad news and bad share-price performance, investors in the superbank need all the good news they can get. Thank Warren Buffett for at least some of the upswing.

Big-four roundup
Before we delve into the trials and travails of JPMorgan, let's have a look at where its peers and the markets are so far today:

  • Bank of America is opening strongly, up 2.43% already.
  • Citigroup has bounced up more than half a point, too, up by 1.04%.
  • Wells Fargo is also up on this first day of trading, by 0.42%.

The markets are so far mixed, with the broader S&P 500 up by 0.15%, the narrower Dow Jones Industrial Average down 0.03%, and the Nasdaq way out in front: up 1.14%.

St. Warren weighs in
JPMorgan finished last week down 2.48%, due primarily to two pieces of bad news.

At the beginning of the week, the bank announced that co-chief operating officer Frank Bisignano left to become CEO First Data Corp, a global payments processor. Bisignano rose to prominence at JPMorgan in the wake of last year's London Whale trading scandal, and was one of CEO Jamie Dimon's key lieutenants. 

Then on Friday, The New York Times broke the news that the country's biggest bank is under investigation by the Federal Energy Regulatory Commission for "manipulative schemes" in the California and Michigan electric markets. As part of the matter, Blythe Masters, the head of JPMorgan's commodities business, was singled out as having given "false and misleading statements" under oath.  

And there's another looming issue for the bank that is surely weighing on investors' minds and that may hinder a bounce back this week: Jamie Dimon is facing a proxy vote at the bank's May 21 shareholder meeting over splitting the roles of COB and CEO, both of which he now holds, at least in part as a result of the previously mentioned London Whale debacle.

Dimon has done nothing but produce for JPMorgan, and investors -- like myself -- have just cause to worry what a restructuring of his role might due to future profits. The proxy vote is non-binding, but it could pressure the board to make the change regardless. 

Bu the stock may be up today as much as it is on news that Berkshire Hathaway CEO and investing guru Warren Buffett has weighed in on the looming proxy vote issue, clearly offering his support for Dimon to stay in both roles. According to The Wall Street Journal, JPMorgan isn't in Berkshire's portfolio, but is in Buffett's private portfolio. Thank you, St. Warren.

But despite Buffett's welcome, don't expect too much out of JPMorgan as an investment for the next few weeks, until investors have the chance to see where at least some of this is shaking out. And as always, Fools, remember that you're in this for the long term.

Check in on your stocks once a month, or even once a quarter, and leave the short-term thinking for the day traders. Your portfolio will thank you, and so will your blood pressure. 

Fool contributor John Grgurich owns shares of Citigroup and JPMorgan Chase. Follow John's dispatches from the bleeding heart of capitalism on Twitter @TMFGrgurich.

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