California has opened its own antitrust investigation into Google, according to three people familiar with the matter, adding to the pressure on the search giant, which is already under investigation by the justice department and a number of other states. The move by the California attorney general comes amid increasing scrutiny by congress and foreign regulators of Google's marketing practices and acquisitions that have made it the world's largest search engine and most profitable online advertising company. Since September, attorneys general from 48 states, Puerto Rico and the district of Columbia have announced antitrust investigations into Google, focusing on the company's dominance in the advertising technology market. In the past 10 months, the Texas-led investigation has expanded to other aspects of the company's business, including its conduct in the search market. source