New stock in Warren Buffett's portfolio and closing of current positions in many stocks

Warren Buffett doesn't have much of an appetite for many stocks lately. Berkshire Hathaway's (BRK.A) (BRK.B) latest quarterly report showed that Buffett and his team sold $7 billion worth of shares and bought just $1.7 billion worth of shares. Meanwhile, Buffett now controls a record $157 billion in cash, the vast majority of which he has invested in short-term US Treasuries.

While investors already knew some of what Buffett and his team were selling in Berkshire's portfolio, based on the company's third-quarter report and other filings with the Securities and Exchange Commission (or SEC), we finally have insight about the exact changes they made. in its latest quarter with its 13F filing, which reveals the company's assets as of the end of November.

Berkshire Hathaway requested confidentiality on at least one stock purchase last quarter, and the SEC granted it. So there's one mystery stock that Warren Buffett and his team have been buying.

The Biggest Changes in Berkshire's Portfolio

Sale of 10% of its stake in Chevron. We learned this from the disclosure in the third quarter earnings report. As of the end of September, the portfolio held company shares worth $18.6 billion.
Sale of 15% of its stake in Hewlett Packard. We learned this from the Form 4 disclosures that require Berkshire to disclose changes in ownership of companies in which it owns more than 10%. The company ended September with shares worth $2.6 billion, but continued to reduce its position in October.
Selling 100% of its position in Activision. Although investors knew that Berkshire no longer owned Activision following its acquisition by Microsoft, it appears that Buffett sold the remaining shares before the deal closed in October.
The 13F also revealed several positions where Berkshire completely exited its positions in General Motors, Celanese, Johnson & Johnson, Procter & Gamble, Modelez and United Parcel Service.

Some positions have been cut, including:

66% stake in Markel, giving the company $233.7 million worth of shares at the end of the quarter.
67% of Globe Life, leaving him with shares worth $185.4 million at the end of the quarter.
5% stake in Amazon, leaving it with $1.3 billion worth of shares at the end of the quarter.
A 5% stake in Aon, leaving $1.3 billion worth of shares at the end of the quarter.
The portfolio also received a shakeup from Liberty Media's spinoff of the Atlanta Braves and a reclassification of its track stocks.

It's worth noting that all of these newly revealed sales are relatively small. Berkshire hasn't made any major changes to its portfolio. In the end, the company sold a total of $7 billion worth of shares out of a $318 billion portfolio.

Berkshire only reported one truly new 13F stock. She bought 9.7 million shares of Sirius XM (SIRI 1.03%).

At the end of the quarter, the stake was worth about $44 million, representing about 0.01% (1/10,000) of the total portfolio value. So it wasn't that big of a purchase.

The vast majority of Berkshire's $1.7 billion in stock purchases last quarter were for new, undisclosed mystery stocks.

We can get some clues from Berkshire's third-quarter earnings report. The company reported that the cost basis of its investments in banking, insurance and financial equity securities increased by approximately $1.2 billion. Sales from Globe Life, Markel and Aon will also bring that figure down slightly, so it equates to $1.7 billion in purchases.

One reason Berkshire might want to keep its new asset confidential is because it wants to continue buying shares of the company. Because changes in its portfolio are so widely watched, any disclosure could cause the stock price to rise significantly. Sirius XM shares rose as much as 15% the day after Berkshire filed its 13F report.

In other words, if you can figure out what Buffett and his team bought last quarter, you can invest before the Oracle of Omaha.