Ironclad Inc., the maker of a contract automation service used by the likes of Dropbox Inc. and Fitbit Inc., this morning announced that it has raised $50 million in fresh capital. 

Y Combinator’s Continuity fund led the investment with participation from Emergence Capital. They were joined by Sequoia Capital and Accel Partners, which backed Ironclad’s previous $23 million funding round back in January. 

Five-year-old Ironclad’s namesake cloud service enables corporate legal teams to cut the amount of time they spend on managing contracts. The service provides a consumer-grade interface that allows nontechnical users to create workflows for automating the most repetitive parts of the document handling process. Legal teams can customize a contract’s text fields, specify the parties who need to sign or approve it and store the agreement in a centralized archive once it’s finalized.

Ironclad also provides more advanced automation options for complex deals. The service can, among other things, automatically adjust the list of stakeholders who must approve an agreement based on the input signatories provide when they’re filling out the contract.

A set of built-in document management features helps legal teams keep all this information organized. Ironclad provides a search function that lets lawyers look up documents with natural-language queries, while allowing administrators to limit what data each user may access based on their role. Team leads, in turn, can employ analytics tools baked into the service to keep tabs on metrics such as staff productivity.

Ironclad’s particular mix of automation and productivity features has turned out to be a hit. The startup more than doubled its customer base over the past year, an uptick in demand that led to revenues tripling during the same period.

Ironclad will use the new funding from Y Combinator and its other blue-chip backers to boost product development. The startup has already been pursuing a high-speed engineering roadmap: In conjunction with the funding news today, Ironclad announced the launch of Workflow Designer, a new point-and-click tool for processing contracts. 

“Our newest investors bring a depth of later stage company experience and a vision for what cloud companies will look like in the future,” said Ironclad Chief Executive Officer Jason Boehmig (pictured, left, with co-founder Cai GoGwilt). “Our new funding will fuel continued product innovations, like our new Workflow Designer, which is accelerating contracting time by 85% for our customers.”

Photo: Ironclad