Average Co-Inventor Count = 3.20
ph-index = 4
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. Duncan Industries Parking Control Systems Corp. (4 from 11 patents)
2. Datakey, Inc. (1 from 18 patents)
4 patents:
1. 5841369 - Parking meter with peripheral functions
2. 5806651 - Coin discrimination system
3. 5805083 - Electronic parking meter operating system
4. 5526662 - Cashless key and receptacle system