![Seiko Shirasaka](data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" width="16" height="16" fill="%231b1b1b" class="bi bi-person-fill" viewBox="0 0 16 16"><path d="M3 14s-1 0-1-1 1-4 6-4 6 3 6 4-1 1-1 1zm5-6a3 3 0 1 0 0-6 3 3 0 0 0 0 6"/></svg>)
Seiko Shirasaka
Director/Board Member at
SAKURA RUBBER CO., LTD.
Net worth: 42 M $ as of 2026-08-30
Profile
Seiko Shirasaka was the founder of Synspective, Inc. and held the title of Director.
Mr. Shirasaka is currently an Independent Outside Director at Sakura Rubber Co., Ltd. since 2016 and a Professor at Keio University since 2010.
Known holdings in public companies
| Company | Date | Number of shares | Valuation | Valuation date |
|---|---|---|---|---|
SYNSPECTIVE INC. 3.36% | 2025-12-30 | 4,500,000 ( 3.36% ) | 42 M $ | 2026-08-30 |
Seiko Shirasaka active positions
| Companies | Position | Start |
|---|---|---|
| SAKURA RUBBER CO., LTD. | Director/Board Member | 2016-05-31 |
Keio University
 Keio University Other Consumer ServicesConsumer Services Functions as a College/University | Corporate Officer/Principal | 2010-03-31 |
Former positions of Seiko Shirasaka
| Companies | Position | End |
|---|---|---|
| SYNSPECTIVE INC. | Founder | - |
Experiences
Positions held
Active
Inactive
Listed companies
Private companies
Connections
77
1st degree connections
3
1st degree companies
Male
Female
Members of the board
Executives
Linked companies
| Private companies | 3 |
|---|---|
Sakura Rubber Co., Ltd.
 Sakura Rubber Co., Ltd. Miscellaneous ManufacturingProducer Manufacturing Engages in firefighting and disaster prevention & aerospace, industrial supplies and real estate leasing businesses | Producer Manufacturing |
Keio University
Keio University Other Consumer ServicesConsumer Services Functions as a College/University | Consumer Services |
Synspective, Inc.
 Synspective, Inc. Telecommunications EquipmentElectronic Technology Develops, manufactures and operates SAR satellites | Electronic Technology |
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