Average Co-Inventor Count = 4.20
ph-index = 3
The patent ph-index is calculated by counting the number of publications for which an author has been cited by other authors at least that same number of times.
Company Filing History:
1. Koh-I-Noor Rapidograph, Inc. (3 from 52 patents)
2. Koh-I-Noor Rapidgoraph, Inc. (1 from 1 patent)
4 patents:
1. 4552483 - Device for covering an oblong opening in a housing
2. 4496958 - Drawing pen exchanger for computer controlled drawing machines
3. 4489333 - Device for exchanging objects in particular writing instruments
4. 4282536 - Process and apparatus for automatic drafting devices