Billionaire Warren Buffett, chairman and CEO of Berkshire Hathaway, has built his fortune on strategy, carefully deciding how to spend and invest his money.

And as it turns out, he's also been strategic when it comes to buying holiday gifts for his family.

According to Buffett's former daughter-in-law Mary, now 68, Buffett switched from "always giving $10,000 in hundred-dollar bills" to each of his relatives, to giving $10,000 in stock instead. Mary was married to Buffett's son Peter from 1980 to 1993.

One season, "there was an envelope with a letter from him," Mary told ThinkAdvisor in October 2019. "Instead of cash, he'd given us $10,000 worth of shares in a company he'd recently bought, a trust Coca-Cola had."

Mary says that in the letter, Buffett told each family member they could either cash in the shares or keep them. Mary told ThinkAdvisor she kept the stock.

"I thought, 'Well, [this stock] is worth more than $10,000.' So, I kept it, and it kept going up. Then, every year when he'd give us stock ... I would just buy more of it, because I knew it was going to go up," she said.

Buffett isn't the only famous stock gift-giver: In 2017, Kanye West gave Kim Kardashian West over $100,000 in stock in companies like Apple, Amazon and Disney. On her Instagram, Kardashian West revealed the gift included 920 Disney shares and around 995 shares in Adidas.

Buffett is also known to give friends and relatives sweets from See's Candies – in fact Buffett loves See's so much that Berkshire Hathaway purchased the company in 1972.

As for gifts Buffett would like to receive, there aren't any, according to Mary.

"The first year [Peter and I] were married, I realized, 'Warren is very rich. Therefore, he doesn't want anything,'" she said. "I didn't know what to get him, so I put together our music company's balance sheet to show him that we were making money." (According to Mary's LinkedIn profile, she and Peter founded post-production music company Independent Sound.)

A representative for Buffett did not immediately respond to CNBC Make It's request for comment.

To give stocks

Stockpile stock e-gift card; prices vary from $1 to $2,000

Stockpile allows customers to buy gift cards that recipients can redeem for fractional shares of stock in various companies and ETFs, that go into a Stockpile brokerage account. There is a $2.99 fee for the first e-gift you buy, and subsequent ones are 99 cents. Plus there is a credit or debit card fee of 3%.

Buffett's favorite See's Candy

See's Candy 10 oz Peanut Brittle; $13.00

In addition to giving See's Candy to friends and family, Buffett and his business partner, Charlie Munger, are known to snack on See's peanut brittle during Berkshire's annual shareholders meetings, according to the candy company.

This story has been updated to reflect changes in pricing.

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