What happened

Shares of U.S. retailer Dillard's (DDS 1.56%) rose as much as 46% in early trading on Monday. That massive price increase didn't stick around for long, with the stock up "only" by a third or so at 10:30 a.m. EDT today. Clearly, investor sentiment turned higher here in a big way, a shift that was largely driven by Ted Weschler.   

So what

Don't feel bad if you don't know the name Ted Weschler off the top of your head. But you are highly likely to know his boss, Warren Buffett, and his employer, Berkshire Hathaway. Weschler is one of Buffett's key lieutenants and handles a portion of Berkshire's investments. When he invests in something, with his own cash, it can have a big impact on the stock. And that's exactly what happened with Dillard's today.    

Three women with bags shopping in an outdoor retail area

Image source: Getty Images

Weschler disclosed that he had personally acquired 1.081 million shares of Dillard's stock, or just under 6% of the retailer's common shares. The news was also reported by Barron's on Friday after the market closed for the day, boosting Wall Street's awareness of the information. Based on today's gain, it's likely that this investment has already been pretty decent for Weschler. Investors are clearly pilling in behind him hoping that his bet on Dillard's will be fruitful for them, too.   

Now what

If you are considering Dillard's stock because of the big gain, step back and take a moment. Nothing has changed at the company other than the fact that a well-heeled investor has bought shares and Wall Street has tagged along behind him. There's likely a lot of positive news priced in here with such a massive increase at this point. Long-term investors should probably examine the fundamentals themselves (very closely) before following along like a lemming.