Jones spoke at a public hearing on the proposed $54 billion merger Tuesday in San Francisco.
Jones is the chief regulator for a small segment of the California health care market. He has the power to block the merger or demand concessions from the companies.
He says his biggest question is whether the merger will help or harm consumers.
Anthem and Cigna officials say the combined company would have lower costs, more products and higher quality.
Some consumer advocacy groups are urging Jones to block the sale, others want him to impose conditions that protect consumers.
Jones is a Democrat running for attorney general in 2018.