The four large-cap Internet companies—Google, (NSDQ: GOOG) Yahoo, (NSDQ: YHOO) eBay, (NSDQ: EBAY) and Amazon—collectively added more than 5,600 net new employees in Q3, and Lehman analyst Doug Anmuth’s Internet Inside Weekly (PDF only, not online) takes a closer look at hiring trends at these companies. Some interesting trends from it:
—Employee costs remain the largest component of overall cash operating expenses (Amazon (NSDQ: AMZN) may be an exception) and quarter-to-quarter changes in headcount can meaningfully impact cost structures, and therefore margins.
—During 3Q07, Google added 2,130 new employees, compared with 1,548 additions in 2Q07. This represented 15% growth Q/Q and 70% growth Y/Y. Google new employee numbers will fall in 4Q and into early 2008.
—Yahoo added 1,200 employees during 3Q, representing 10% growth Q/Q and 24% growth Y/Y. This compares with 700 new hires in 2Q, which represented 6% growth Q/Q and 18% growth Y/Y. Q3 hirings were primarily due to an organic increase within product development, though recent acquisitions were also a factor.
—Amazon added 1,400 net new employees during 3Q, well above the 600 hires added in last year’s period. This represented approximately 10% growth Q/Q and 19% growth Y/Y, and compares with 2Q headcount growth rates of 3% Q/Q and 13% Y/Y. Management noted that headcount additions during 3Q07 were predominantly related to the company’s fulfillment center operations.

The chart on the right gives a good summary in numbers (click on it to get a bigger version).