Warren Buffett owns a little-known stock portfolio worth nearly $6 billion. These are the portfolio's top 10 stock holdings.

• Through Berkshire Hathaway, Warren Buffett owns an under-the-radar stock portfolio worth $5.9 billion.
• New England Asset Management is a subsidiary of General Re, which Berkshire bought for $22 billion in 1998.
• These are the top 10 holdings of NEAM's $6 billion stock portfolio, according to SEC filings.

Billionaire investor Warren Buffett's moves in the stock market are widely followed by investors as they try to replicate his success.

Through Berkshire Hathaway, Buffett and his lieutenants manage a portfolio of stocks worth nearly $300 billion as of September 30.

But Buffett also owns an under-the-radar stock portfolio worth $5.9 billion through Berkshire Hathaway. The portfolio is managed by New England Asset Management, which provides investment management services that are tailored to insurance companies.

New England Asset Management was acquired by General Re in 1995. Then, in 1998, Berkshire Hathaway acquired General Re for $22 billion, making New England Asset Management a wholly owned subsidiary of Buffett's conglomerate.

While Buffett has no influence over the $6 billion portfolio managed by New England Asset Management, the portfolio does have some striking similarities to Buffett's $300 billion stock portfolio.

For one, it's extremely concentrated, with its top 10 positions making up 92% of the portfolio. The top 10 holdings of Berkshire Hathaway's main stock portfolio make up 87% of its assets.

Additionally, New England Asset Management has a knack for owning some of its stocks for decades, and there's considerable overlap in the names of stocks owned by New England Asset Management and Buffett.

Apple, for example, is New England Asset Management's top holding and was first purchased by the fund in 2013. That's three years before Buffett decided to add Apple to his portfolio, which is also now its largest position.

These are the top 10 holdings of New England Asset Management. This list is as of September 30 and excludes ETFs and focuses on individual stocks. The ETFs excluded from this list include the SPDR S&P 500 ETF, the iShares Core S&P 500 ETF, the iShares MSCI Europe ETF, and the iShares Select Dividend ETF. 

10. Cisco Systems

Ticker: CSCO
Market Value: $8.7 Million
Percent of Portfolio: 0.15%
Date First Acquired: Q1 2001

9. JPMorgan

Ticker: JPM
Market Value: $11.2 million
Percent of Portfolio: 0.19%
Date First Acquired: Q1 2001

8. Bank of New York Mellon

Ticker: BK
Market Value: $11.7 million
Percent of Portfolio: 0.20%
Date First Acquired: Q1 2015

7. Microsoft

Ticker: MSFT
Market Value: $13.0 million
Percent of Portfolio: 0.22%
Date First Acquired: Q1 2001

6. Diageo

Ticker: DEO
Market Value: $38.7 million
Percent of Portfolio: 0.66%
Date Acquired: Q3 2005

5. HP

Ticker: HPQ
Market Value: $410.6 million
Percent of Portfolio: 6.99%
Date First Acquired: Q3 2021

4. Chevron

Ticker: CVX
Market Value: $637.9 million
Percent of Portfolio: 10.85%
Date First Acquired: Q1 2001

3. US Bancorp

Ticker: USB
Market Value: $668.5 million
Percent of Portfolio: 11.37%
Date First Acquired: Q1 2001

2. Bank of America

Ticker: BAC
Market Value: $687.1 million
Percent of Portfolio: 11.69%
Date First Acquired: Q3 2017

1. Apple

Ticker: AAPL
Market Value: $2.83 billion
Percent of Portfolio: 48.13%
Date First Acquired: Q1 2013