Cisco has finally won control of videoconferencing leader Tandberg by snagging 91.1 percent of the company's shares.

It was a long-fought battle. Cisco had to raise its initial $3 billion offer and extend the acceptance deadline three times in order to gain control of the company. Cisco's initial offer, made on 1 October, was rejected by more than 90 percent of Tandberg shareholders.

At the expiry of the third acceptance deadline, Cisco said it controlled 89.1 percent of Tandberg shares. The condition for ownership of the company was control of 90 percent of Tandberg shares, but Cisco waived this condition based on a two percent stake it acquired in November, according to published reports.

Of the 140 or so acquisitions Cisco has made in the past 16 years, Tandberg was perhaps the most challenging. Two groups of shareholders controlling 30 percent of the company rejected the initial $3 billion offer. And then two investment firms representing other stakeholders issued a public letter to Cisco CEO John Chambers and Senior Vice President Ned Hooper stating that Cisco was undervaluing the company and spelling out specific reasons why it should hike its offer.

Cisco relented on 16 November6, raising its offer for Tandberg to $3.4 billion and extending the acceptance deadline to 1 December from 18 November. Cisco then extended the acceptance deadline again to 3 December.

By acquiring Tandberg, Cisco is looking to fill out its desktop and midrange videoconferencing product portfolio. Its high-end TelePresence offerings can cost hundreds of thousands of dollars and are apparently too costly and elaborate to scale downmarket, as Cisco initially intended.

Cisco will also now become the market leader in videoconferencing. Tandberg is the current leader with about 40 percent share, ahead of Polycom, according to Wainhouse Research.

Cisco views video as the "killer app" that will fill up bandwidth and drive equipment upgrades into the next decade.