For security, the card was limited to storing 125 EUR of available electronic cash (originally 5,000 BEF).
[2] In August 1998, Proton World International was founded, a joint venture between Banksys, Visa, American Express and EGR.
[3] In 2001, the Australian company ERG bought the remaining shares of Proton World and became the sole shareholder,[4] making a $50 million loss two years later by selling it to STMicroelectronics.
[5] Proton saw limited success in Belgium, despite being available on commonplace on parking meters, pay phones, and within convenience stores; possibly due to a poor understanding of the system.
[7] Customers are requested to offload the charged amount back onto their bank account before the expiration date.