Warren Buffett notches a $4 billion gain on Occidental Petroleum in under 6 months - as the energy stock nears a 4-year high

Thanks to the energy stock surging to a four-year high, Warren Buffet's company has racked up a $4 billion gain on the oil and gas company.

A Markets Insider analysis shows that the investor's conglomerate poured $10 billion into the oil and gas explorer and producer between February 28 and August 8. It had 186 million shares, or 20% of the company, which ranged from $41 to $60.

Since the beginning of the year, the share price of the company has increased by about 83%. It is currently trading at around $75, its highest level since November of last year. A 42% gain on the stock in less than a year is what the team has achieved.

The company has said it will buy more shares. It obtained regulatory approval to increase its stake in the fossil-fuel specialist to 50% or double the previous 25% ownership limit.

The conglomerate has $10 billion of preferred stock of the company. It received warrants in exchange for financing the energy company's takeover of Anadarko in 2019.

Vicki Hollub outlined her plan to refocus the company, which led to a warm relationship between the two companies. She wants to increase shareholder returns.

During the annual shareholder meeting in April, Buffett said that Vicki Hollub's words made no difference.

He said that it was a good place to put the money of the company.

At the time, the 91-year-old investor highlighted rampant speculation and manic trading of the company's shares, which enabled him to buy a large amount of the company's stock.

Oil-and-gas companies have benefited from higher energy prices this year due to Russia's invasion of Ukraine.

They own $26 billion of the oil major's shares and are confident that prices will stay high for a while.

Steven Check has a $655 million stake in Warren Buffet's company. He explains why he's still bullish on the stock, and compares the stock-buying spree of Warren Buffet to previous years.