A Phillips 66 logo is seen on a gas pump as a car is filled a Beck's station in Princeton, Illinois.

Berkshire Hathaway continues to unload its stake in Phillips 66, disclosing Monday the sale of another 36 percent of its holdings in the stock since the end of the second quarter.

In a filing with the Securities and Exchange Commission, Warren Buffett's conglomerate said it held 22.186 million shares, down around 12.5 million from holdings reported as of the end of June. In the second quarter, Berkshire unloaded 24 percent of its stake. It cut more than 40 percent of its shares in the energy company in the first quarter, when it sold 35 million shares back to Phillips 66 to bring its holding below 10 percent.

At the time, Berkshire said it would continue to be a long-term holder of Phillips 66.

The most recent move reduces Berkshire's stake to 4.8 percent of Phillips 66, from 7.5 percent.