Stocks were mostly flat today as the S&P 500 hit a new record high at 1617.50, but the Dow Jones Industrial Average (DJINDICES:^DJI) was down slightly by five points, or 0.03%. No major news was pushing markets as investors continued to digest last week's bullish announcements, including the federal employment report, and on monetary policy both at home and in Europe. There were no economic reports released today, and no major earnings reports out.

After hours, the Senate approved the Marketplace Fairness Act, taking an important step toward imposing an Internet sales tax that would help brick-and-mortar retailers compete on a level playing field with the likes of online heavyweights such as Amazon.com. The law could also be a boon for big-box chains like Best Buy. The bill will now move on to the House where Republicans are divided on its passage.

On the Dow today, Bank of America (NYSE:BAC) was the big winner, gaining 5.2% after settling a long-standing dispute with insurer MBIA over mortgage bonds issued during the housing bubble. Shares of MBIA finished up 45% as B of A agreed to pay $1.7 billion to resolve the legal matter. Investors clearly considered the settlement a victory for MBIA, and Bank of America has taken several steps in recent months to escape the litigious hangover from its 2008 acquisition of mortgage lender Countrywide, having paid a total of $16.9 billion on five settlements in this year alone.

UnitedHealth (NYSE:UNH) shares were also looking brighter today, gaining 2.2% after JPMorgan Chase upgraded its rating on UnitedHealth and Humana to overweight, saying the insurance providers should be able to grow their Medicare Advantage enrollment in spite of potential reimbursement cuts. UnitedHealth shares have bounced up and down this year as the government has changed its expected cut to the program from 8% to 4%.

Finally, Merck (NYSE:MRK) was the worst performer on the Dow, falling 1.5%. There was no company-specific news out on the drugmaker today, but investors are continuing to flee the stock after a disappointing earnings report last week. Merck's revenue dropped more than expected after going over the patent cliff on its Singulair asthma medication, and the market seems worried about where future revenue growth will come from.

Fool contributor Jeremy Bowman has no position in any stocks mentioned. The Motley Fool recommends UnitedHealth Group and owns shares of Bank of America. 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.