Probably not:
Berkshire Hathaway A shares:
http://finance.google.com/finance?q=NYSE:BRK.A
Mkt Cap: 199.53B
Berkshire Hathaway B shares:
http://finance.google.com/finance?q=NYSE:BRK.B&hl=en
Mkt Cap: 200.38B
Market evaluation of Berkshire Hathaway is around 200 billion USD. I think GIC(US$330 billion) and Temasek(US$159.2 billion) have comparable or bigger portfolios. But looking at track record, I think Buffett is the better fund manager, hahaha.