Google Inc. (NASDAQ: GOOG) announced it will acquire online advertising network DoubleClick Inc. for $3.1 billion. The purchase will strengthen Google’s position in the Internet advertising market. It is also the biggest purchase in Google’s history, happening six months after the $1.65 billion YouTube deal.

Microsoft Corp. (NASDAQ: MSFT) was involved in the bidding too, but they backed out after the auction price was higher than $2 billion.

With its more than 1,500 corporate clients, DoubleClick should help Google expand into the markets of print, radio and TV advertising and it should help provide better ad targeting.

Related posts:

1. EU approves Google’s DoubleClick acquisition
2. Google adds $2.6 billion in advertising revenue
3. Google to acquire Feedburner?
4. Facebook deal with Microsoft or Google
5. Internet ad revenue reached $21 Billion in 2007