This article examines the pronouncements regarding property rights in the environmental impact assessment regime in Chilean law to determine the protection of the activities authorized by the Public Administration. The analysis begins with the pronouncements of the General Comptroller Office (administrative case law). The judgments of the courts of justice (judicial case law) are then examined. The contrast in the pronouncements of the two state bodies reveals relevant differences in the interpretation of the rights of the holders. In the General Comptroller Office, the environmental impact assessment has created vested rights to a continuity of operation. As a result, certain economic activities cannot be evaluated environmentally, and the regime of others already evaluated cannot be subject to modification. Judgments of the courts of justice diverge from the criteria above through restrictive interpretations of the administrative rights that may be acquired by the holders of activities in this environmental protection instrument.