It's been almost exactly one month since Warren Buffett's Berkshire Hathaway (BRK.A 1.18%) (BRK.B 1.30%) announced its latest stock holdings -- and The Motley Fool decided to check in on how the portfolio of the Oracle of Omaha's company is doing.

Buffett has had a solid run since the end of September, and based on the roughly $92 billion that Berkshire held, the company has seen the value of its holdings grow by a little more than $4.5 billion, a return of almost 5%. That narrowly trails the S&P 500's return of 5.5% over that same time period.

Of course, Buffett's investing ability isn't characterized by 55 days of returns, but Berkshire Hathaway has had a number of remarkable performers since September:

As a matter of fact, of the 43 companies in the Berkshire Hathaway portfolio, more than 13 have had returns of 10% or more since September. The biggest winner, Media General (NYSE: MEG), has seen its stock rise by more than 50%, and it's up more than 400% on year.

Here's the entire list of companies delivering remarkable returns for Buffett:

Company

Portfolio Value
(Millions)

Return
(9/30-12/15)

Media General

$66

52.4%

Phillips 66 (PSX 0.91%)

$1,571

23.8%

DISH Network

$25

18.4%

MasterCard

$272

17.1%

Chicago Bridge & Iron

$647

15.8%

General Electric

$14

12.3%

VeriSign

$558

12.1%

DirecTV

$2,183

11.5%

Precision Castparts

$449

11.4%

General Motors

$1,439

11.3%

UPS

$5

11%

American Express

$11,450

10.8%

ExxonMobil (XOM 1.15%)

$3,449

10.8%

Despite its big move, Media General represented only 0.07% of the portfolio -- $66 million out of a total $92 billion -- so it didn't move the needle much. This gain was driven in large part by its reporting of third-quarter earnings that surpassed analyst expectations. The stock soared and has been on quite the run ever since.

Next in line was Phillips 66, where the 24% increase in its stock price represented an unrealized gain of nearly $375 million for Berkshire Hathaway. Although Phillips 66 saw its third-quarter earnings drop compared with last year, the company did announce a 25% dividend increase, a move that investors celebrated. Considering that Phillips 66 is the nation's largest refiner in a rapidly expanding American energy market, it's seemingly well positioned for future success, too.

Although it has the "smallest" return -- if you can call an 11% return small! -- the final company I'll mention is ExxonMobil. In the middle of November, Berkshire Hathaway disclosed that it had been steadily adding to a position in the world's largest oil company over the past few months, which was actually one of the contributing factors in sending the stock higher. Buffett's known ability to spot high-quality companies trading at fair prices sent many people pouring into this giant.

In all, the past two and a half months have been kind to Buffett -- and when you consider that Berkshire Hathaway is up almost 30% on the year, he'll probably be sleeping pretty easy this holiday season.