In the complaint filed Friday in Orange County Superior Court, the company's principal subsidiaries, Signal Landmark and Hearthside Homes Inc., allege that the commission made an about face regarding its prior findings and decision to approve development of the entire 208 acres of the mesa. Signal owns the property, and Hearthside is the developer.

In all, the complaint lists four causes of action against the commission: 1) administrative mandate; 2) inverse condemnation; 3) violation of due process under the US and California constitutions; and 4) violation of equal protection under both constitutions.

The plaintiff states that the Ccmmission has violated the Coastal Act by failing to balance the social and economic needs of Orange County citizens and that the designated conservation area and exactions per an amendment to the original plan, introduced at the public hearing held on Nov. 16, constitute "takings."