Complex sentence: Russell was a lifelong supporter of the Sierra Club, Sigurd helped found the progressive housing cooperative of Ladera, and Varian Associates had innovative employee policies that were ahead of its time.
Split into simpler sentences: Russell was a lifelong supporter of the Sierra Club and Sigurd helped found the progressive housing cooperative of Ladera. Both were noted for their progressive political views, and Varian Associates had innovative employee policies that were ahead of its time.