Box, a publicly traded cloud content and storage company, plans to spend $55 million to acquire Dutch startup SignRequest, a cloud-based electronic signature service. The deal should close by the end of April. The acquisition helps Box close the “document lifecycle” by keeping files (and any required actions) within its secure platform. Box will develop on top of SignRequest’s technology, building in the e-signature capability under the name ‘Box Sign’. As of this summer, Box Sign should be included in business and enterprise plans. Eventually existing SignRequest users will be prompted to switch their accounts over, but the Amsterdam-based company will continue operating as is and taking on new customers. Since its founding in 2014, the startup has reached over 500,000 users. As for Box, the Californian company says it serves more than 100,000 businesses, including 69 percent of the Fortune 500.