JPMorgan Chase ( JPM), the nation's third-largest bank, reported a 68% gain in profits, providing a good start to the fourth-quarter earnings season for the nation's banks.

In the quarter, JPMorgan earned $4.53 billion, or $1.26 a share, compared to $2.7 billion, or 76 cents a share, a year ago. The most recent quarter includes a $622 million after-tax gain stemming from the sale of the bank's corporate-trust business.

Excluding the sale and other items, the New York-based bank, on an operating basis, earned $3.9 billion, or $1.09 a share, compared with $2.6 billion, or 74 cents a share a year ago. Revenue rose 14% to $16.9 billion from the year-ago period.

Earnings and revenue both topped Thomson Financial consensus estimates. Analysts were looking for operating earnings of 95 cents a share on revenue of $16 billion.

In premarket trading, shares were up 36 cents to $48.75.