What do letters like "FH" mean on pigment ink labels?

[SuppliesMaster]

 Does anyone know what the letters that are under the color of the ink mean?  In this image it's FH, but I've also seen others. What does it mean?? 

[shadowsports]

Greetings,

Maybe it's a lot number.  If you'd like a definitive answer, I'd contact Canon support.  1-800-652-2666

[normadel]

Since these are obviously NOT Canon inks, why not ask the supplier/manufacturer?

[SuppliesMaster]

They are on Canon's official sites.  I don't think your answer makes much sense. 

[normadel]

I don't see anything that indicates Canon.

So if they are on "Canon's official sites",  why not ask Canon? What official sites are you looking at?

[SuppliesMaster]

And isn't this an official canon community?? 

You can go to the canon page whatever you like. And start to notice this detail. 

I didn't look at it before. Now that I noticed it, I have doubts. And I can't find any information about it. 

That's why I wrote here. Because perhaps someone had already gone through the same doubt. 

[normadel]

This is not an "official Canon community".  It is a forum of canon USERS. It is NOT Canon Corporation.

Don't know what your doubts are.  Call Canon.

[Stephen]

This is the official Canon Community, hosted and moderated by Canon USA. 

The product photos above are for special ink cartridges for large format imagePROGRAF machines. If Canon USA sells these inks directly to consumers, it's not by normal channels because I can't find a resource on them indicating we sell them directly.

That being said, I realize you're just curious, and I'm sure it means something, but I can't find any documentation. Which printer are they for exactly? Can you share either a link or a screenshot of the site from where you bought them?