Tom Walker wrote in a message to Jasen Betts:

->  TW> Becasue the Printer will NOT work without the proper chip in the
->  TW> Cartridge.

-> if they can use a generic chip (like a rom or a microcontroller)
-> then the tooling cost shouodn't be too high,

 TW>  I suspect that HP and the others putting chips in their Ink
 TW> Cartridges are smarter then to use a chip that one can easily buy.
 TW> It of course cound be Reverse engineered but that is an additional
 TW> cost added to the tool up for the chip itself.

Doesn't matter what the chip is,  if they have any sort of code in it, 
then they can claim intellectual property rights and keep others from
making something that's in there.  It could be a cheap little serial prom
chip or whatever,  those things don't cost much in bulk,  and it'd lock the
market for refills...

The makers doing that sort of thing irritates the heck out of me,  though, 
and I won't buy *anything* from them if I have a choice about it.

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