(Bill Pugliano/Getty Images)
On Friday evening, billionaire investor Warren Buffett, the founder of Berkshire Hathaway, disclosed that he had purchased a massive stake in oil refinery Phillips 66 (PSX).
As of Friday's share price close at $77.23, Buffett's stake is valued at more than $4.47 billion.
Buffett had been aggressively buying shares of Phillips 66 since Wednesday of this week.
Earlier this month, Buffett had indicated in his 13-F filing that he was building a new position.
Here's a rundown of Buffett's purchases over the last few days.
Here's the Phillips 66 stock chart for this week:
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