Boone Pickens’ group lowered its stake in Unocal.

Mesa Partners II, led by the Mesa Petroleum chairman, lowered its stake in the Los Angeles-based energy and mineral resources company to 14.8 million shares, or about 12.7%. The group said it sold about 1.07 million shares, less than 1%, in accordance with an agreement reached earlier in the year when Unocal successfully rebuffed the Pickens group’s takeover effort. Mesa also said it pledged its Unocal stock and other assets to obtain a $250-million revolving credit line from a group of banks led by Citibank.