Robert Benmosche, who led American International Group Inc. for half a decade, said an emerging challenge from Warren Buffett’s Berkshire Hathaway Inc. hasn’t amounted to much so far.

Buffett’s firm recruited AIG executives beginning last year to expand commercial coverage under the Berkshire Hathaway Specialty Insurance brand. Benmosche said those who left AIG didn’t buy into his efforts to increase collaboration.

“They took their bitterness out on AIG and wanted to make a big show,” Benmosche, 70, said in an interview with Bloomberg Television’s Betty Liu airing today. “They went over there and, boy, are they really not showing us anything at all.”

Berkshire has targeted excess and surplus lines, or business coverage that can’t be obtained in regulated markets. AIG is dominant in the E&S market, with Berkshire playing a lesser role, according to Moody’s Investors Service. JoAnn Lee, a spokeswoman for BH Specialty, declined to comment on Benmosche’s remarks.

Insurers have been attracted to E&S because rates are rising for the coverage, Moody’s said in a report this month. That compares with lower prices for natural-disaster coverage, which had been an area of focus for Omaha, Nebraska-based Berkshire. Buffett relies on insurance units like Geico and General Re to generate premium revenue that he can invest in stocks and takeovers.

Berkshire hired AIG executives Peter Eastwood, David Fields, Sanjay Godhwani and David Bresnahan last year for what Buffett called a “big time” expansion into business coverage.

AIG Commitment

The venture is being led by Eastwood, who had been chief executive officer of AIG’s property-casualty business in the Americas and previously led an E&S insurer for the company. AIG’s stock slid 3.3 percent on April 26, 2013, when the departures were reported.

Buffett’s company agreed to stop recruiting from AIG for a year after the New York-based insurer raised objections, Benmosche said.

Departing managers had an obligation “to protect company property and protect company’s interests and clients,” he said. “That’s a commitment you make.”

Benmosche discussed AIG’s recovery from a 2008 bailout during interviews last month at his estate in Croatia. He also spoke about how he dealt with a 2010 cancer diagnosis and eventually decided to accelerate his departure from AIG as the prognosis worsened. Peter Hancock, who led the property-casualty operation and picked replacements for the departing executives, took over as AIG’s CEO on Sept. 1.

Travel Insurance

Berkshire has resumed hiring AIG managers at the unit, adding Marc Breuil and Marcus Portbury in Asia, a person familiar with the matter said last month. Buffett’s firm yesterday said Brian O’Neill joined from AIG to lead an expansion into fidelity and crime insurance. BH Specialty has also taken on AIG by expanding into travel insurance.

The Lloyd’s of London market is the top provider of excess and surplus coverage in the U.S., followed by AIG, according to Moody’s. Sales at AIG dropped about 4.2 percent last year to $4.83 billion, while the figure at Berkshire climbed 39 percent to $560.9 million.

“The business that they’re picking off is unusually profitable,” Meyer Shields, an analyst at Keefe Bruyette & Woods, said of Berkshire in a phone interview. “It’s not hurting Berkshire at all on the underwriting side.”

Benmosche, who led AIG from 2009 until he was replaced by Hancock, 56, pushed AIG’s businesses around the globe to work more closely together. That curbed autonomy for some executives and helped fuel the departures, he said.

“They wanted to be left alone and run their own franchise,” Benmosche told Liu. “The fact is that they disagreed with a very simple philosophy. We have to be one AIG.”