Warren Buffett's Berkshire Hathaway Inc. is getting ready to split the company's Class B shares next Thursday as part of its plan to buy Burlington Northern Santa Fe Corp.

The 50-for-1 stock split, which shareholders will vote on Wednesday, will boost the liquidity of Berkshire's stock, which is one of the nation's most expensive. And that will increase the chances that the Omaha-based company will one day be part of the S&P 500 index.

Berkshire's Class A shares, which were selling for $97,600 Friday afternoon, are not being split.

Class B shares, dubbed "Baby Berkshires," were first issued in 1996 to meet demand from investors who couldn't afford Berkshire's original stock.