Pindrop helps businesses avoid getting scammed on the phone by analyzing both the audio of a call and the metadata it has about a caller. After raising a total of $47 million since its launch in 2012, the company today announced that it has raised a $75 million Series C round led by Google Capital.

Other participants in this round include Google Ventures, Citi Ventures, and Felicis Ventures, as well as its Series A lead investor Andreessen Horowitz and Series B lead Institutional Venture Partners.

Pindrop says its technology is currently in use by a number of insurance companies, government agencies, retailers, and three of the four largest banks in the United States. In total, the company has now screened more than 360 million calls.

The service looks at some basic data about each call, including where it comes from, and whether it’s from a landline, cell phone or a VoIP number (most fraudulent calls apparently come over VoIP lines). In addition, it also analyzes the audio of the call. It looks for evidence of frequency filters and codec artifacts, for example, and analyzes the calls for packet loss and dropped frames.

Based on this, the service then generates a risk profile for every call. If the system flags a call as potentially fraudulent, the agent can then ask additional security questions, for example.

Pindrop tells me it plans to use the new funding to expand internationally and increase its investments in research and new product development. The company already has a ten-person office in the UK, but now plans to expand its presence in the EMEA region. It’s already working on setting up operations in Latin America and then plans to move to Asia Pacific later this year.