B2B ad spending totaled $14.39 billion in 2006, up 1.4 percent from $14.19 billion in 2005. The top 100 B2B advertisers accounted for $6.76 billion (or 47 percent) of that amount, up 3.0 percent from $6.56 billion in 2005, according to BtoB's analysis of data from TNS Media Intelligence, reports MarketingCharts.

Also, internet ad spending by B2B advertisers increased 17.0 percent from 2005, reaching $1.38 billion in 2006, BtoB said.

According to BtoB's analysis:

• Telecom led B2B ad spending in 2006:
  • AT&T was the No. 1 B2B advertiser, spending an estimated $419.4 million, up 10.4 percent from the previous year.
  • Verizon Communications was the No. 2 B2B advertiser; it spent an estimated $405.9 million on B2B advertising last year, up 8.7 percent from the previous year.
  • Sprint-Nextel was the No. 3 B2B advertiser in 2006, spending $277.1 million, down 31.2 percent from 2005, when it spent $403.1 million to promote its new brand.
• High-tech companies were also high on the list of top B2B advertisers:
  • IBM Corp. was No. 4, spending $236.3 million on B2B advertising, down 17.5 percent from 2005.
  • Hewlett-Packard was the No. 5 B2B advertiser in 2006, with B2B ad spending of $219.6 million - up 5.8 percent over 2005.
  • Microsoft was No. 6 in 2006; it spent an estimated $213.6 million on B2B advertising, down 0.6 percent from 2005.

• Monster Worldwide, FedEx Corp., Citigroup, and JP Morgan Chase & Co. rounded out the top 10 B2B advertisers of 2006.
• Among the host of B2B ad spenders increasing their budgets last year was Apple, which increased its B2B ad spend 350.2 percent to $85.0 million, moving from No. 115 in 2005 to No. 24 in 2006.
• Dow Chemical increased its B2B ad spend 481.8 percent, to $61.2 million, moving to No. 33 from No. 195 the previous year.

The BtoB report also ranks the top 50 B2B internet advertisers of 2006:

• Monster Worldwide was No. 1. It increased B2B internet ad spend 79.6 percent from 2005, to $101.6 million.
• HP was No. 2, boosting its B2B online ad spending 10.7 percent, to $60.9 million.
• Vonage Holdings Corp., was No. 3, decreasing its B2B iternet ad spending 32.7 percent. to $46.4 million.
• Other top 10 B2B Internet advertisers last year were IT career site Dice Inc., Dollar Thrifty Automotive Group, AT&T, Microsoft, Capital One Financial Corp. and CareerBuilder.