Big Banks had a busy week last week, riding the wave of a choppy market still spooked by QE3 taper worries. This week looks pretty good by mid-morning Monday, with the Dow, S&P 500, and the whole financial sector glowing green.

Things could change at any moment, of course, considering the volatility lately. But Bank of America (NYSE:BAC), Citigroup (NYSE:C), JPMorgan Chase (NYSE:JPM), and Wells Fargo are all up, with B of A rising safely above the $13 per share mark once again.

More legal troubles
The latest news for the biggest banks isn't very good, however, and it comes in the form of an action by the European Commission charging B of A, Citi, and JPMorgan -- in addition to 10 other banks -- with blocking exchanges Deutsche Boerse and the Chicago Mercantile from entering the credit derivative market. These breaches of European Union antitrust rules are alleged to have occurred within the past decade.

As for Bank of America, it had its share of headlines last week, with a couple of items that might be of interest to investors.

Bloomberg reported that B of A is outsourcing its property valuation reports to India, purportedly to save some money. Cutting costs is sure to make investors smile, but the article notes that, along with the hefty paychecks the U.S.-based appraisers command, there is a matter of qualification. Reviewers in this country are licensed, inferring a level of expertise above a simple checklist, which is what B of A is providing to the workers in India. Will this new cost-cutting measure land B of A in court, further down the road?

Also, the brouhaha over B of A's alleged deviousness regarding processing refinances through the government's Home Affordable Mortgage Program has caught the eye of National Mortgage Settlement monitor Joseph Smith, who may be planning to make some trouble for the big bank as well.

Still, the bright economic news regarding upticks in construction and manufacturing activity for May seems to be lifting the entire sector, at least for the moment.

Will Bank of America be able to maintain its momentum this week? Whether it does or not, keep in mind that it's the overall performance of a stock that really counts. As Foolish, long-term investors, we recognize that one-day changes in share price don't make or break an investment. Even stocks have good days and bad days, so it's important to realize that sometimes they're not portents of dire news, but merely squiggles we can safely ignore. 

Fool contributor Amanda Alix has no position in any stocks mentioned. The Motley Fool recommends Bank of America and Wells Fargo. The Motley Fool owns shares of Bank of America, Citigroup, JPMorgan Chase, and Wells Fargo. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.