Investors appear to like Berkshire Hathaway stock in the $60s and even the $70s more than they liked it at roughly $3500 a share. 

Berkshire shareholders approved a 50-for-1 stock split of Berkshire's Class B shares yesterday.  Trading began today.

The lower price is seen as an opening for small investors who couldn't afford the old four-figure price tag.  (The Associated Press quotes a number of eager buyers in a piece this morning.)

After the first thirty minutes, the Baby Bs are up 4.8 percent to $72.88 from the split-adjusted close of $69.50 ($3475 per share pre-split.)

That puts them on track for their highest close since November, 2008.

Current price:

At yesterday's meeting, Warren Buffett told shareholders that the increased trading volume and liquidity for the Class B shares after the split could make it the key driver of Berkshire's market value.  "The B may be the tail that wags the dog now."

That may be the case today.  Berkshire's Class A shares are also up almost 5 percent as of 10a ET.

Current price:

There also appears to be another factor at work here. 

Ravi Nagarajan on the Rational Walk is giving the credit for today's rally to Buffett's comment yesterday to Bloomberg that Berkshire's stock at the "low end" of its valuation. 

Berkshire closed just over 4 percent higher in yesterday's trading.

The Class A shares picked up 2.6 percent on Tuesday.  For the week so far, it is up over 10 percent.

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