Omaha, Nebraska-based insurer Berkshire Hathaway revealed Wednesday (May 15) that it has invested in Swiss counterpart Chubb. 

The Associated Press reported that Warren Buffett's company disclosed the nearly $7 billion investment, equivalent to almost 26 million shares, in a quarterly filing with the Securities and Exchange Commission, saying that the funding has been discreetly developed over the past nine months.

It is unclear if Buffett himself or one of Berkshire's two investment managers made the Chubb investment, but generally, Buffet handles all shares worth $1 billion and above. 

By the end of March, Berkshire said that it held almost 26 million Chubb shares, equivalent to 6.4% of the Zurich-based firm. Chubb's shares increased by 7%, or  $271.82, in after-hours trading after the investment was revealed.

CNN reported that Chubb made headlines last March after it underwrote former US President Donald Trump's almost $92 million appeal bond in the defamation lawsuit filed by E Jean Carroll.

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Investors have been constantly following Berkshire's portfolio due to Buffett's successful track record over the past few decades. For some projects, the company will wholly purchase Chubb in the future, just like they have done to several other firms, like Geico and General Reinsurance. 

CFRA Research analyst Cathy Seifert said that Chubb is now one of the ten biggest holdings in Berkshire's portfolio, adding that the business mixes Berkshire employs was "highly complementary."

Aside from buying shares from Chubb, Berkshire also sold off over 116 million Apple shares, or 13% of its total stake, this quarter. The sale still left them with 790 million more shares of the creators of the iPhone, which Buffett told shareholders at its annual general meeting would remain with the company in a long-term holding.

Buffett also told shareholders it sold off all its 7.5 million Paramount Global shares at a loss.

VCPost reported earlier this month that Chubb has also prepared a $350 million payout after the Francis Scott Key Bridge in Baltimore collapsed earlier this year.

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