DHInfrastructure supported preparation of expert testimony on behalf of PG&E. As part of this work DHInfrastructure: 1.) Constructed a database of market bid prices and production costs; 2.) Calculated economic withholdings of power marketers; 3.) Identified anomalous bidding strategies used by power marketers that constituted tariff violations; 4.) Analysed the bidding behavior of specific sellers in order to evaluate and rebut the opposing party’s arguments; 5.) Provided on-going analytical support and reporting using the constructed models.