May 12, 2015 · 3 minutes

Moving it well beyond its already unicorn status -- last year the company was valued at $1.6 billion -- online secure signature startup DocuSign announced today that it has raised $233 million in a Series F round of funding. The company, which has raised $433 million to date, plans to use the new capital to expand its DocuSign Global Trust Network to more international markets.

Founded in Seattle and headquartered in San Francisco, DocuSign is one of the pioneers in online e-signatures. Its cloud-based electronic signature technology is used by more than 100,000 companies in industries including real estate, law, bio-pharma, and other document intensive businesses.

While its products are used by more than 50 million users in 188 countries, DocuSign has targeted markets in Europe, Asia, and beyond to expand its already fast user growth. Currently, the company claims that it adds 50,000 new e-signature users every day.

"What's next for DocuSign is really the $233 million question, but it really comes down to, first, expanding our global business," said chief marketing officer Brad Brooks. He added that the company also has plans to continue the development its e-signature products — especially in the mobile space -- build out its sales and marketing teams, and to expand to more verticals, including sales and human resources.

"Globally, we are just heating up. We want to get more people aware of exactly what we are doing and how we are doing it," he said.

Bringing its products to more international market poses some challenges for the company, which has already gained acceptance as a legal, secure way to sign digital documents in the U.S. and some other markets. "There are some specifics around legal matters, which is that verifying the authenticity of the digital entity that you are verifying, whether it's a person or business, is a bit different in Europe than it is in the U.S.," said Brooks.

The company's Global Trust Network is a platform that serves as a common way to verify identities and to make approvals from a legal standpoint. Through strategic acquisitions in Europe and partnerships with companies like SAP, the platform serves as a way for international customers to make sure that they are complying to region-specific laws surrounding legal signatures and online identification. Building a foothold in Europe and beyond puts the company at the forefront of the global e-signature market.

"I analyze markets all day, and this market has almost limitless potential because what these guys are doing has allowed them to become the standard in what we are calling 'digital transaction management,'" said Enrique Salem, who sits on DocuSign's board of directors for Bain Capital Ventures.

"Think about every non-financial transaction, think about how many times you have to sign something that has started in a digital format that you have to print out, sign, and then send back," Salem said. "These guys have figured out how to keep things digital."

A bit of an interesting wrinkle to the funding news is that the round was led by two of the five entities that make up Bain Capital. Brookside is Bain's public equities group, while Bain Capital Ventures is the firm's VC operation. In addition to the Bain backing, Generation Investment Management, ClearBridge Investments, Cross Creek Advisors, Iconiq Capital, Wasatch Advisors, LLP, Wellington Management Company, Sands Capital Ventures and others, took part in the funding.

While the company declined to discuss the valuation that led to its $233 million fundraise, its was valued at $1.6 billion after its $85 million fundraise last year. Obviously, the Series F investment pushes the company to an even higher valuation. But with an enterprise focus and a path to legitimate revenue, Docusign seems to have a lot more going for it than many other Silicon Valley unicorns. Its investors obviously feel that way.

"You look at all the great companies over the last five to 10 years, this is not a company that is hype-based. This is a real company, that has real customers who use the product every day, and love it," said Bain Capital Ventures' Salem.