Light Signatures, Inc.
28Patents
0Active
28Granted
34Portfolio score
Filing activity: Jun 22, 1981 → Jul 25, 1988
Most-cited patents
| Patent | Title | Area | Cited by | Status |
|---|---|---|---|---|
| US4423415A | Non-counterfeitable document system | Emerging Cross-Sectional Technologies | 281 | Expired |
| US4811408A | Image dissecting document verification system | Physics | 175 | Expired |
| US4476468A | Secure transaction card and verification system | Physics | 161 | Expired |
| US4748679A | Weighted-pixel characteristic sensing system | Electricity | 129 | Expired |
| US4795890A | Device authentication system for on and off line use | Physics | 122 | Expired |
| US4689477A | Verification system for document substance and content | Emerging Cross-Sectional Technologies | 102 | Expired |
| US4816824A | Merchandise verification and information system | Physics | 85 | Expired |
| US4806740A | Magnetic characteristic identification system | Physics | 68 | Expired |
| US4807287A | Document authentication method | Physics | 67 | Expired |
| US4568936A | Verification system for document substance and content | Physics | 61 | Expired |
| US4546352A | Non-counterfeitable document system | Physics | 59 | Expired |
| US4785290A | Non-counterfeitable document system | Physics | 49 | Expired |
| US4837840A | System for verifying authenticity of various articles | Physics | 39 | Expired |
| US4651150A | Merchandise verification and information system | Physics | 31 | Expired |
| US4558318A | Merchandise verification and information system | Physics | 31 | Expired |
| US4489318A | Non-counterfeitable document system | Physics | 30 | Expired |
| US4630845A | Authentication document system | Physics | 28 | Expired |
| US4675669A | System of issuing secure documents of various denomination | Physics | 28 | Expired |
| US5023923A | Programmable sensor aperture | Physics | 25 | Expired |
| US4686527A | Verification system for document substance and content | Physics | 23 | Expired |
| US4663622A | Non-counterfeitable document system | Physics | 19 | Expired |
| US4656473A | Secure card and sensing system | Physics | 15 | Expired |
| US4739322A | Merchandise verification and information system | Physics | 13 | Expired |
| US4916294A | System for reliable digital recording on unreliable magnetic media | Physics | 13 | Expired |
| US4635054A | Operator interactive device verification system | Physics | 12 | Expired |
Source: USPTO / EPO open patent data. Counts and citation impact are objective bibliographic measures.