Warren Buffett’s Berkshire Hathaway confirmed a 20.2% stake in Occidental Petroleum (US:OXY). Berkshire now controls a 28.6% stake, or 272.2 million shares, including warrants, of Occidental.

Berkshire's stake passed 10% in March and topped 15% in May. 

Here is the complete timeline of Buffett's purchases. 

There are also reports Buffett has regulatory approval to acquire up to 50% of Occidental Petroleum, although he's not expected to take a controlling interest now. 

Occidental Petroleum beat earnings and revenue expectations in late February, but the stock barely reacted to the news. However, two days later, the stock price erupted following a shareholder-friendly update. At the same time, it was revealed a few days after that Buffett’s Berkshire Hathaway (US:BRK.B, US:BRK.A) amassed a considerable stake in the company.  

How Much Occidental Stock Will Buffett Buy?

The fact that Buffett continues accumulating the stock raises an obvious question: How much of the firm will Buffett acquire, and in time, will he buy all of Occidental Petroleum?

With Buffett, you can never rule out a complete acquisition. Not when Berkshire ended last quarter with more than $100 billion in cash and short-term investments. And he’s had a more complicated relationship with Occidental than some investors likely realize. 

In 2019, Occidental outbid Chevron (US:CVX) for Anadarko, mainly thanks to facilitating a deal with Berkshire Hathaway. As part of the deal, Berkshire received 100,000 preferred shares valued at $100,000 each — or $10 billion in total — and these shares pay an annual yield of 8%. Further, Berkshire received warrants to purchase up to 80 million shares at $62.50 apiece (as mentioned in the 13G filing above). 

Why is that information important? While we certainly can’t rule out Buffett & Co. further increasing their stake in Occidental, he may be comfortable with simply maintaining a stake over 20%. By doing so, Berkshire can report a proportional share of Occidental's earnings within its own earnings report. 

Further, Berkshire continues to collect its annual dividend payment of $800 million, which is no small sum even for Buffett -- a lover of dividends. 

Lastly, Buffett’s Berkshire owns stakes over 20% for several publicly traded firms, including Kraft Heinz (US:KHC), Davita (US:DVA), American Express (US:AXP) and Liberty Sirius XM Group Series A (US:LSXMA). 

So there’s always the possibility that Buffett will keep that strategy alive and maintains an outsized position in Occidental Petroleum. At the same time, he continues accumulating a larger stake, which does not rule out a potential acquisition down the road.