BRK's derivative activities seem to be winding down

From Saturday's shareholder meeting.

Question: Who will manage Berkshire's derivatives book when you go?
"I don't think there will be much of a derivatives book when I go," Mr. Buffett says. He says managing it "is not a
big deal." Most of the company's ongoing derivatives activities are in the energy business.
He adds that the company "hit a home run" with its investment managers, Todd Combs and Ted Weschler, who
would be among those managing derivatives after Mr. Buffett leaves. But "the rules have changed" regarding
collateral presentation for derivatives -- Berkshire has in the past written contracts that don't force it to post
collateral to its trading partner, but now doing so is mandatory -- and so the company is unlikely to dabble in
derivatives.