Berkshire Hathaway (BRK-B) gained 2.09% last week. I recently highlighted that Berkshire Hathaway sold off a $100 million position in National Oilwell Varco (NOV) and a $600 million position in Phillips 66 (PSX) last quarter — despite the current low oil prices. Berkshire Hathaway disclosed late Friday that it now has a $4.5 billion stake in Phillips 66 (PSX) — a 10% stake at 58 million shares. It turns out that Buffett was actually buying shares under a confidentiality agreement with the Securities and Exchange Commission (SEC) so others would not copy his moves. BRK-B is a HOLD.