they would sign a patent royalty agreement or make ZIP sign a royalty agreement. That would put pressure on all the other companies to do the same. If they can't be coerced, then IDSY needs to sue them and sue ZIP. Hopefully, BEFORE ZIP is owned by Avis.
If IDSY really wanted to get aggressive with their patent and a lawsuit, they could start suing the cities that give free parking to these companies. It would get the attention of a lot of people and really put pressure on the companies to settle.
They could also go after the manufactures of the embedded GPRS modems that are used by many of the companies. CAMP comes to mind
"If they can't be coerced, then IDSY needs to sue them and sue ZIP. Hopefully, BEFORE ZIP is owned by Avis."
Great idea, moron! Maybe you should buy more IDSY instead of announcing that you're dumping your shares. How many thousands have you lost already? IDSY patents are worthless. No volume means no interest. FLIP FLOP FLIP FLOP. YOU POOR SCHMUCK! NEVER FORGET. - I OWN YOU!