In Morrison Knudsen Corp. v. Hancock, Rothert & Bunshoft (1999) 69 Cal.App.4th 223, a subsidiary corporation contracted with a water district for engineering services to relocate a road for a dam project. (Morrison, supra, 69 Cal.App.4th at p. 227.) The law firm Hancock, Rothert & Bunshoft (Hancock) served as attorneys for the subsidiary's parent corporation and were later retained by the water district to investigate the subsidiary's work on the road relocation project. (Id. at pp. 227-228.) On appeal from the trial court's order disqualifying Hancock, the appellate court discussed "the circumstances in which parent and subsidiary corporations may be treated as one entity under California conflict of interest rules." (Id. at p. 240.) Quoting a formal opinion of the California State Bar Standing Committee on Professional Responsibility and Conduct, the court stated that a parent and subsidiary should be treated as one if: (1) "'a corporation is the alter ego of another entity or has sufficient unity of interests,'" or (2) "'the attorney has obtained confidential information directly from the nonclient subsidiary under circumstances where the subsidiary could reasonably expect that the attorney had a duty to keep such information confidential ... .'" (Morrison, at p. 241.) To determine whether a sufficient unity of interests exists, attorneys must "'evaluate the separateness of the entities involved, whether corporate formalities are observed, the extent to which each entity has distinct and independent managements and boards of directors, and whether, for legal purposes, one entity could be considered the alter ego of the other.' ." (Morrison, supra, 69 Cal.App.4th at p. 241.) Applying that test to the parties before it, the Morrison court noted Hancock received confidential information during the course of its work for the parent corporation substantially related to the water district's claim against the subsidiary corporation. (Morrison, at p. 245.) Additionally, the parent corporation "controlled the legal affairs of the subsidiary," the parent's personnel administered the subsidiary's contract with the water district, and the water district was aware of the parent corporation's involvement. (Id. at p. 246.) Based on that evidence, the court affirmed the trial court's finding that the parent and subsidiary had a unity of interests such that they should be treated as one entity for conflict of interest purposes. (Id. at pp. 247-248.)