(Apple, Wal-Mart and Berkshire Hathaway article updated from March 17 with new information on the market-cap of all the companies, as well as news related to the passing of an Apple director.)NEW YORK ( TheStreet) -- A game of market capitalization leapfrog has been playing out between some of the biggest U.S. companies. Last week, it was noted by some market commentators that Apple's ( AAPL) share rally -- as the iPad made its way to the launch pad -- had helped Apple's market capitalization to leap ahead of retail empire Wal-Mart ( WMT) and legendary investor Warren Buffett's Berkshire Hathaway ( BRK.B). The market capitalization crown didn't remain on Apple's head for long. A Wal-Mart rally through the first two days of the week, begun on the strength of Citigroup upping Wal-Mart shares to a buy, put some distance between Wal-Mart, Apple and Berkshire, in the market cap race. Apple's market cap was back down to $203.2 billion, versus close to a $213 billion market capitalization for Wal-Mart at the open on Thursday morning. Apple shares have lost more than $2 over the first three trading days of the week, after ending last week on a high note. While Apple shares were having trouble defending themselves this week, Taiwanese cellphone maker HTC announced on Thursday that it is planning a vigorous defense against a patent infringement charge that it lifted Apple's iPhone technology, with the CEO of HTC making his first public comments about the Apple lawsuit and saying he was confident that the Taiwanese cell phone maker would prevail in the legal tussle. Apple also received sad news on Thursday morning. Apple director Jerome York, a director since 1997, suffered a brain aneurysm and passed away in a Michigan hospital. York was a former CFO of both IBM ( IBM) and Chrysler. Apple CEO Steve Jobs put out a statement saying, "Jerry joined Apple's board in 1997 when most doubted the company's future. He has been a pillar of financial and business expertise and insight on our board for over a dozen years. It's been a privilege to know and work with Jerry, and I'm going to miss him a lot."