Billionaire Warren Buffett’s Berkshire Hathaway Inc. invested in Johnson & Johnson and Sanofi-Aventis SA this year and may have sold its stakes in Gap Inc. and Lexmark International Inc. The insurance and investment firm bought 1.97 million shares of Johnson & Johnson, the largest maker of medical devices, in the Q1, a filing with US Securities and Exchange Commission showed. In the Q2, Berkshire purchased 488,500 American depositary receipts of Paris-based Sanofi-Aventis, the No. 3 drugmaker. Buffett, often buys stakes in companies he deems undervalued. Shares of Johnson & Johnson, based in New Brunswick, New Jersey, increased 6.3% this year, underperforming the 7.9% gain in the Standard & Poor’s 500 Pharmaceuticals Index. Sanofi-Aventis’s stock fell 2.8% in the Q2, its first quarterly decline in two years. Berkshire, based in Omaha, Nebraska, said it had been allowed to keep the Johnson & Johnson stake confidential until today and is still omitting certain holdings. The company didn’t mention Gap, the largest US clothing chain, or Lexmark, the No. 2 US maker of computer printers, in the June 30 report. A comparable filing for March 31 showed 10 million shares of San Francisco-based Gap and 2.5 million of Lexmark, which is based in Lexington, Kentucky. Berkshire trimmed its shares of H&R Block Inc., the largest US tax preparer, and boosted its holding of Iron Mountain Inc., the largest seller of records-management services. The H&R Block stake dropped to 11.4 million shares from 16.1 million, while Iron Mountain rose to 5.02 million shares from 3.48 million. (Bloomberg)