C5 Capital said it led a funding round of $51 million for Shape Security, a platform for bot and fraud mitigation, bringing the company's valuation to $1 billion.

Shape Security, based in Mountain View, California, provides online fraud protection for about half of the online banking industry in North America, as well as numerous other industries. 

"This investment will help us scale our international operations and fuel our AI development," Derek Smith, co-founder and CEO of Shape Security, said in a release from C5. "Our new and returning investors, coupled with our continued track record of growth, underscore our vision to protect all enterprises from fraudulent Internet transactions."

Beyond C5, other investors in the round include Kleiner Perkins, HPE Growth, Norwest Venture Partners, Focus Ventures, JetBlue Technology Ventures, Top Tier Capital Partners and Epic Ventures. The investment brings the total funding raised by the firm to $173 million.