Coro, a startup that offers a cloud-based AI-powered cybersecurity platform for mid-market companies, has announced $75 million in funding from Energy Impact Partners, a green-tech investor that has backed a number of cybersecurity and enterprise startups.

The company, which started out in 2015 as a consumer-focused device security business called Coronet, pivoted to enterprise in 2019. Coro's platform covers device monitoring and oversight of activity across users, email, networks, data and apps. It also remediates any malicious activity when it is detected.

Coro has grown its annual recurring revenues by 300% each year for the last four and currently has around 5,000 customers.

Mid-market businesses which Coro is focused on, often fall into a grey area when it comes to software, as they are too big for SMB products but lack the budgets to use products built for larger enterprises.

In addition, mid-market firms are becoming more aware of the need to secure their systems. One report found mid-market companies to be 350% more likely to face a cyberattack than larger businesses, and as a signal of the opportunity here (and the problem), in general, mid-market companies are becoming more aware of the issues.

The Series C2 round follows the company's $60 million Series C last year, which valued Coro at $500 million; the new funding brings the valuation to $575 million. The funds will be used to invest in R&D, acquire smaller cybersecurity firms and hire more staff.