Our Team
Officers・Advisors
Co-Founder and CEO
Jim Weisser
Jim is a serial entrepreneur and angel investor, Jim has founded a number of companies and has lived in Japan since 1993.
A graduate of Rice University with a Bachelors in Chemical Engineering, he has founded multiple companies in Japan. Just prior to establishing SignTime in 2020, Jim started PBXL KK, which provided cloud PBX services to Japanese businesses. PBXL KK was acquired by Cisco Systems/BroadSoft, Inc. in 2015. He was also involved in business planning and development activities as Regional Manager of the Cloud Calling Business Unit at Cisco Systems.
Jim was featured in "The Quiet Comeback II", a book on Japanese entrepreneurship and is currently a co-chair of the American Chamber of Commerce in Japan's DX (Digital Transformation) Committee. He is also a judge in the Asian Entrepreneur Awards, a competition established by Tokyo University (Todai).
He is also big fan of Umeboshi!
Co-founder
Jonathan Siegel
Jonathan Siegel is a co-founder of SignTime. Jonathan is a serial entrepreneur who has founded companies in e-commerce, cloud services, and digital signatures and is currently managing partner at Xenon Ventures. He also holds multiple patents related to digital signatures. Jonathan is also a serial learner, having completed an MBA, a law degree, and a helicopter license. His book, ‘The San Francisco Fallacy - The Ten Fallacies That Make Founders Fail’ has been translated into Japanese.
Advisor
Yoshimasa Aikawa
Yoshimasa Aikawa is currently an executive advisor to SignTime. At the beginning of career, he joined Fujitsu Kyushu Systems in 1982 as a Systems Engineer, and progressed through the ranks, eventually becoming Executive Director. Subsequently, he became President of Fujitsu Cloud Technologies in April 2017. He has extensive cloud experience both from his time at Fujitsu and while establishing Aitcz. Yoshimasa provides ICT consulting services to a variety of companies. Yoshimasa became an advisor to SignTime in May 2022.
Advisor
Hirokazu Sampei
Hirokazu was the first president of Docusign Japan and is a highly regarded thought leader in the field of Japanese e-signatures and electronic contracting. He is also a data communications and IP expert, having worked at Cisco designing Internet infrastructure for telecommunications carriers and has extensive experience in Cloud and SaaS platforms, working with Polycom, A10 and DocuSign, among other leading tech firms. In 2019, he founded meUP, Inc. in 2019, which consults on retention and acceleration programs for businesses. He is an avid and experienced rally car enthusiast, and became an advisor to SignTime in March 2021.
SignTime Members
Web Sales Manager
Heijeung
Engineering Manager
Nikolay
Engineering Manager
Midori
Account Manager
Ami
Our Philosophy
- Vision
Enable an agile workforce by eliminating Muda, Mura, and Muri - At SignTime, we believe agility starts with clarity. Our vision is to help companies eliminate the three enemies of productivity—Muda (waste), Mura (inconsistency), and Muri (overload)—to enable faster, more focused work across Japan and the world. (This vision is inspired by the Toyota Production System.)
- Mission
Bring All Analog Workflows Online. - We exist to end the breaks in digital flow—when work that begins online slips into paper, or static PDFs, only to be re-digitized at a cost to speed, clarity, and accuracy.
Our mission is to preserve and extend true digital smoothness from start to finish, replacing repetition with meaningful results for teams in Japan and around
- Values
-
"Simple is Beautiful"
The best tools get out of your way. We design SignTime so anyone can send, sign, and complete work without training, setup headaches, or clutter. Simplicity means teams can focus on their work—not on learning software. -
"Digital Smoothness First"
Once work starts digital, it should stay digital—never losing speed, searchability, or automation to paper, stamps, or static PDFs. We build to eliminate the “digital → analog → digital” trap, preserving the clarity and efficiency of true end-to-end workflows. -
"Fast Where It Matters"
Speed is not an extra—it’s the expectation. From salescontracts to HR onboarding, SignTime removes unnecessary waits and repetitive steps so decisions can move forward in seconds or minutes, not days. Time saved is time you can reinvest in customers and growth….or in yourself. -
"Built for Business"
We focus on the workflows that make companies run—sales, HR, operations, and approvals—especially in traditional industries where DX can transform how people work. Every feature exists to move business forward with less friction and more certainty. -
"Trust & Compliance by Design"
Security, auditability, and legal enforceability are non-negotiable. We build compliance into every process, so clients can accelerate work without compromising control or confidence. Trust is the foundation of everything we do.
About
| Company Name | SignTime K.K. / サインタイム株式会社（In Japanese） |
|---|---|
| Founded | |
| Type of Business | Developing and operating e-signature service SignTime |
| Location | Toranomon Hills Business tower 15F, 1-17-1 Toranomon, Minato-ku, Tokyo 105-6415, Japan |
