On a per-share basis, operating earnings increased to to $2,302 per Class A share from $1,615 in the year-earlier period.
Including $1.1 billion in recorded earnings for investments and derivatives, Berkshire's net income increased 51 percent to $4.89 billion vs. $3.25 billion in 2012's first quarter.
Buffett has repeatedly warned investors that the mark-to-market gains and losses Berkshire records for its investments and derivatives each quarter are "usually meaningless" because the company has no intention of unwinding those positions anytime soon.
(Read more: Buffett on the Fed, His IBM Stake and His First Tweet)
Berkshire's book value, Buffett's favored method of putting a value on the company, increased by 5.5 percent from the end of 2012 to $120,525 per Class A share at the end of March.
Tomorrow, Buffett will be answering questions in front of an estimated 30,000 shareholders when Berkshire holds its annual meeting in Omaha.
Those shareholders should be fairly happy. Berkshire's Class B shares closed up 1.25 percent on Friday at a fresh all-time high of $109.00 That's a year-to-date increase of 21 percent.
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