http://h20000.www2.hp....2632486#A0

The reason HP has developed this software is to counteract the counterfeit market. This is stated by HP here...

What is HP Toner Cartridge Authentication?

HP Toner Cartridge Authentication is free software from HP that validates that the installed cartridge(s) are Original HP LaserJet toner cartridges. Customers will have improved visibility into the status of their cartridges (new, used, not genuine), thus helping them avoid becoming victims of fraud or counterfeit.

Hp is defining all cartridges non-OEM as counterfeit, if it's being sold as new OEM. This is stated by HP here...

If the customer unknowingly bought counterfeit, they can respond to the authentication information by returning the cartridge to the store to request a refund or replacement. Counterfeit cartridges are remanufactured or clone cartridges sold as new, Original HP LaserJet toner cartridges at close to the price of a new cartridge.

The key thing..."sold as new, Original HP LaserJet toner cartridges at close to the price of a new cartridge." This could mean "clones" are not counterfeit.

I think (my opinion)

There is, let's say 10 AM chip manufactures on the market. Each AM chip manufacture has a unique chip signature. So for example...an SCC chip emits a different signature than say a Uninet chip, for the same cartridge.

HP has been gathering these signatures from our AM chips, and has created a database of these signatures. They gather information from the customers cartridge and send it back to HP to compare to there database. HP eludes to this here...

Will HP collect customer information?

When you use the HP Toner Cartridge Authentication software -- printer model, cartridge model and serial number information is transmitted to HP to verify that an Original HP cartridge has been installed. This information will not be stored after the authentication is complete.

HP also states that their Toner Cartridge Authentication software can detect if your cartridge is using "some genuine HP supplies", which could mean all cartridges installed are OEM, such as in a colour laser printer. But could also mean the drum or PCR is OEM. HP states this here...

Authentication Results

After HP Toner Cartridge Authentication has checked your supplies, you might see any of these messages:

No Risks Detected: Your product is using genuine HP supplies.

Risks Detected: Your product is using some genuine HP supplies, but some of the supplies are not genuine HP. If you believe you purchased genuine HP supplies, go to www.hp.com/go/anticounterfeit .

Non-HP Cartridges Detected: None of the supplies are not genuine HP. If you believe you purchased genuine HP supplies, go to www.hp.com/go/anticounterfeit . To understand the benefits of using genuine HP supplies go to www.hp.com/go/learnaboutsupplies .

Conclusion...

If HP is able to detect a "counterfeit" based on chips that are know to be used on counterfeit cartridges, whats stopping them from blocking the cartridges from working in the printer.

And if they deem other chips to be "non counterfeit", such as SCC chips. Whats stopping the counterfeiters from using these chips.

Then HP may have a legitimate reason to "block" all non OEM cartridges from their printers.