Merrill Lynch & Co.’s backlog of investment banking assignments are at a record level, the company’s chief financial officer said Tuesday.

Assignments are higher than earlier this year in every investment banking category, particularly in advisory and debt origination assignments, he said. Conditions for completing the assignments “appear to be more positive” than in the just-ended third quarter, CFO Jeff Edwards said in a conference call with investors.

Merrill earlier reported record net earnings for the third quarter of $3 billion, or $3.17 a diluted share.Excluding a $2 million gain from the sale of its investment management business to BlackRock, net earnings rose 43% from one year earlier to $1.9 billion, or $2 a share. Analysts had forecast operating earnings of $1.47 a share, according to First Call.

Investment banking revenue in the third quarter fell 26% from this year’s second quarter and 3% from one year earlier to $857 million.

Banking activity has picked up since the end of summer, Mr. Edwards said, though it is still not as robust as in the first half of the year. “We are encouraged by our growing backlog,” he said, “and confident in the long-term secular growth story unfolding globally.”

Merrill booked a record 37% of its revenue last quarter from businesses outside America, Mr. Edwards said.

Separately, Mr. Edwards said Merrill expects to increase its share buybacks in the current quarter to levels earlier in the year. The company repurchased 18.3 million shares in the third quarter for $1.3 billion and is authorized by its board to spend another $6 billion on repurchases.

Mr. Edwards also said Merrill will continue to use its excess capital to make acquisitions. Merrill, which owns just under 50% of BlackRock, has made more than 30 acquisitions and strategic alliances in the past three years. In September, it agreed to pay $1.3 billion to buy the First Franklin subprime mortgage originations and servicing businesses from National City Corp.