Top five takeovers that shook the tech world

Microsoft last week launched a hostile $44.6bn takeover bid to buy web giant Yahoo!. If the deal goes ahead it will be the latest in a line of multibillion-dollar mergers and acquisitions the tech sector has witnessed in recent years.

See below for silicon.com's pick of the most significant tech takeovers...

1. AOL Time Warner, $164bn, 2000:
Web giant AOL and entertainment company Time Warner joined forces in 2000 in a massive deal worth $164bn. A year after the initial bid was made the US Federal Trade Commission gave its approval to the deal in January 2001.

The partnership didn't get off to a great start when the new company reported a loss of $99bn in 2002 after the value of its America Online ISP division fell dramatically.

2. Worldcom and MCI, $37bn, 1998:
Telecoms giant Worldcom bought MCI, the long distance operator, in 1998 for around $37bn. In the process, Worldcom had to pay BT almost $7bn to buy out the UK company's 20 per stake in MCI.

Unfortunately Worldcom filed for bankruptcy in 2002, becoming the biggest corporate failure in US history after it failed to survive a brutal consumer price war.

3. HP and Compaq, $25bn, 2001:
When tech services and hardware group HP bought PC maker Compaq, the move was hailed as the biggest takeover in the history of the sector. The tie-up meant the combined company could challenge the revenues of IBM. HP boss Carly Fiorina became CEO of the new company.

4. Symantec and Veritas, $13.5bn, 2004:
Symantec bought storage specialist Veritas Software in a $13.5bn deal , forming a powerhouse of security systems and storage management software with annual revenues of around $5bn.

5. Oracle and Peoplesoft, $10.3bn, 2004:
Software giant Oracle has been buying almost everything in sight over the past few years, the biggest acquisition being PeopleSoft in 2004. The company was acquired for around a 10 per cent premium on its closing share price.

Other recent acquisitions by Oracle include Siebel, JD Edwards and most recently, BEA Systems.

And the rest…
Other notable deals worthy of mention include networking and communications equipment-maker Lucent's acquisition of Ascend for $20bn in 1999 and Comcast's purchase of AT&T for a whopping $67bn in 2001. IBM also shelled out the relatively paltry sum of $3.5bn on the consultancy arm of PricewaterhouseCoopers in 2002.