Ericsson said it has acquired Entrisphere, a Santa Clara company providing fiber technology so that people can access broadband.

The amount was not disclosed, but Network World hears a rumor that it was $290 million. For a company that soaked up at least $146 million since launching in 2000, that’s an ok outcome for investors.

This is another story of the staying power of Accel Partners, which backed the company in all seven rounds of financing. It stayed with the company, even as the company restructured over the years. We recently reported how Accel did the same in the case of MetroPCS, and that paid off. This backing stands in strong contrast to some other VC behavior we’ve been reporting about lately.

Other backers included Benchmark, Crosspoint, DAG Ventures, CDP Capital, Capital Communications, Costella Kirsch, Light house Capital Partners, SVM Star, Ontario Teachers Pension Plan and VantagePoint Venture Partners.