Although it finished the quarter very close to Lenovo, HP has given up the top PC vendor position for the first time since the third quarter of 2006. HP is currently restructuring its device business, including PCs, tablets and printers. HP's main concern is achieving a good balance between market share gain and margin protection.

Dell was the No. 3 vendor in PC shipments worldwide in the third quarter of 2012. While Dell suffered a steeper shipment decline than the worldwide average, it was less impacted by the upcoming release of Windows 8 because of its strong focus in the professional market. Dell continues to gradually transform itself from a PC/device supplier to a solution provider.

In the U.S., PC shipments totaled 15.3 million units in the third quarter of 2012, a 13.8 percent decline compared with the same period last year.

"The third quarter has historically been driven by back-to-school sales, but U.S. PC shipments did not increase, not even sequentially, from the second quarter of 2012. Channels were conservative in placing orders," Ms. Kitagawa said. "Professional PC shipments in the U.S. began slowing in the second quarter of this year, and they continued the trend in the third quarter. The results indicate that the replacement peak may have passed in the professional sector."

Four of the top 5 vendors in the U.S. market experienced shipment declines. HP maintained the No. 1 position in the U.S. market despite a shipment decline of 19.3 percent (see Table 2). Lenovo was the only vendor among the top 5 to increase shipments. Both Acer and Toshiba shipments declined significantly due to the tough environment in the consumer market. Apple expected to have a PC shipment decline due to softness in the public market, but the company faced a slowdown in the consumer market.

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