Gonzalez was vice president of finance and administration of Planned Parenthood's Los Angeles affiliate. His suit, filed under the federal False Claims Act, contends he was fired in 2004 after raising concerns about "illegal accounting, billing and donations practices."
The case involves reimbursement to Planned Parenthood for contraceptives under state and federal public health programs.
The alleged overbillings began in the late 1990s. They continued until state law was changed in 2004 to allow Planned Parenthood to bill at a higher rate, said Gonzalez's lawyer, Jack Schuler.
A call to a Planned Parenthood Affiliates of California spokeswoman was not immeditely returned Saturday. However, spokeswoman Ana Sandoval declined to comment to the Los Angeles Times on Friday.