Berkshire Hathaway
Berkshire Hathaway Chairman Warren Buffett seen at the annual Berkshire shareholder shopping day (Photo: Reuters)

It was recently revealed in a government filing that Warren Buffet's Berkshire Hathaway apparently holds a substantial stake in the e-commerce giant Amazon; a stake worth more than $900 million.

The documents revealed that Berkshire was holding 483,300 Amazon shares, a fact that was divulged in its report to the Securities and Exchange Commission. Following the revelation of Berkshire Hathaway's position size, Amazon shares jumped by 0.1 percent.

Based on Amazon's current stock market pricing, the shares Berkshire is holding is worth around $904 million. While the figure may seem substantial, it really just represents around 0.1 percent of Amazon's total market capitalization. Berkshire isn't really even included in the firm's top biggest shareholders.

Apart from Jeff Bezos and his fellow executives, the company with the largest stake in Amazon remains to be The Vanguard Group. The investment firm currently holds close to 30 million Amazon shares or around 6.08 percent of the company.

The firm's shares are estimated to be worth more than $57 billion based on current market prices. Other companies on the list include Fidelity Management & Research, Black Rock Fund Advisors, T Rowe Price Associates, and SSgA Fund Management.

Warren Buffett had previously announced that his firm was making a substantial investment in Amazon earlier in the month. However, the iconic investors did not disclose the size of their position.

The investment was also confirmed during Berkshire Hathaway's annual shareholder's meeting, but its position size was also not disclosed to the public.

The 88-year old business magnate and billionaire clarified during a recent interview that he actually wasn't the one responsible for the investment in Amazon. Buffet, a known fan of Amazon and its CEO, explained that one of his "fellows in the office" was the one that bought Amazon shares.

Reports have indicated that the person he was likely referring to could be either of his two top lieutenants, namely Ted Weschler or Todd Combs.

Both executives currently manage investment portfolios for Berkshire Hathaway estimated to be worth around $13 billion in equities. Buffett also mentioned admitted that he was a big "idiot" for not buying Amazon shares early on in his career.

Apart from revealing its position size in Amazon, the SEC filing also revealed Berkshire Hathaway's position in other firms. It was revealed that the investment firm had increased its stake in JP Morgan Chase by 18 percent to 59.5 million shares. The firm also increased its stake in Red Hat Holdings by 22 percent to 5.1 million shares.