An investment adviser with historic ties to Warren Buffett likely scored a $900 million gain on Wayfair stock in less than 10 weeks

• An investment adviser that traces its origins to Warren Buffett likely netted a nearly $900 million gain on Wayfair in under three months.
• Ruane, Cunniff & Goldfarb bolstered its position in the online home-goods retailer to 5.2 million shares as of March 31, and the Sequoia Fund it manages also built a stake of 1.9 million shares.
• Wayfair's stock price has soared 230% since then, lifting the combined value of those investments from about $380 million to $1.25 billion.
• Bill Ruane founded Sequoia Fund in 1970 at Buffett's request, as the famed investor was closing his partnership to focus on Berkshire Hathaway and wanted Ruane to take on his partners as investors.
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An investment adviser with historic links to Warren Buffett was more daring than the Berkshire Hathaway boss in the first quarter, and as a result it probably scored an almost $900 million gain on a single stock in less than three months.

Ruane, Cunniff & Goldfarb raised its stake in Wayfair by 30% between February 18 and March 31, after boosting its position in the online furniture-and-homeware retailer by 39% in the fourth quarter of 2019, SEC filings show.

The purchases meant it owned 5.2 million Wayfair shares, or 5.5% of the company, at the end of March. Wayfair stock has skyrocketed 230% since then, lifting the value of RCG's stake from about $280 million to $920 million.

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RCG also bet on Wayfair via the Sequoia Fund, the $3 billion mutual fund it manages. Sequoia took a position in the e-commerce group in the third quarter of 2019, then almost doubled its stake to 1.9 million shares by the end of March, SEC filings show. Those shares have surged in value from about $100 million to $330 million.

The upshot is that the combined value of RCG's direct investment and its Sequoia Fund bet has soared from roughly $380 million to $1.25 billion — an $870 million gain in less than 10 weeks..

RCG declined to comment when contacted by Business Insider about the gains.

The adviser traces its origins to 1970, when the late Bill Ruane cofounded the Sequoia Fund at Buffett's request. Buffett was closing his partnership to focus on Berkshire Hathaway, and asked Ruane to take on his partners as investors.

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Buffett's admiration for his former Columbia University classmate is clear. While searching for his successor as Berkshire's investment chief in 2007, Buffett told The Wall Street Journal, "I'm looking for another Bill Ruane."

RCG is a longtime fan of Buffett too. It owned $550 million in Berkshire stock at the end of March, accounting for nearly 9% of its portfolio's total value. Moreover, the Sequoia Fund held $168 million in Berkshire stock on March 31, making up 5.5% of its portfolio.