While prices were crashing Warren Buffett kept increasing his bet on oil

While oil was crashing, Warren Buffett was buying up oil stocks.

Daily regulatory filings dating back to January 6 show that the Berkshire Hathaway CEO has significantly upped his stake in Texas-based energy company Phillips 66.

In the same period, oil prices have plunged to new 12 year lows.

According to the filings, Buffett's purchases have totaled about 5 million shares in the past few days, increasing his stake in the company to about $5 billion.

Phillips 66 shares were up almost 5% in afternoon trading on Thursday and the stock is up 4% since the end of August 2015 when Buffett first disclosed a 10% stake in the company.

Buffett last bought Phillips 66 shares in September. Oil prices have plunged about 30% since then.

(via CNBC.com)