SAN FRANCISCO (MarketWatch) -- Berkshire Hathaway BRK.A, -1.30% BRK.B, -1.45% said late Friday that third-quarter net income came in at $1.06 billion, or $682 per class A share, down 77% from a year earlier when the insurance-focused conglomerate made $4.55 billion, or $2,942 per class A share. Operating earnings, which exclude net realized investment gains and losses, were $2.07 billion, or $1,335 per class A share, in the latest period. The net result included net investment and derivative losses of $1.01 billion, Berkshire said.