Do toner cartridges expire? I just bought one online and the date on box states 2011-09-20

[WestCoastCarlos]

DO TONER CARTRIDGES HAVE A SHELF LIFE OR EXPIRE? 

I recently bought an HP original CB436A laserjet toner cartridge for an older monochrome printer I have (Laserjet P1505). 
The toner cartridge has what I believe to be a lot number and a manufactured date on the side for 2011-09-20.   This makes the cartridge at least nine and a half years old.   The box looks like the original, but of course dated design on it. 

Box is in good shape, and everything seems legit.  Know many times these dealers buy huge lots of them. So this looks well taken care of, just want to make sure the toner will not clump together or other mechanics inside will not have degraded. 
Based on this, I will know if I should return it and try to find something newer.  If this is not a problem at all,

I'd appreciate some input from someone who might have had this same questions.  I buy original HP, because I dont want to deal with the hassle of things not working when you need, this tends to happen when you buy the refurbished, or re-filled "side products" that people sell on amazon or ebay. 

Thanks for any help, possible. 

[Valsimot]

If it works you are fine.

Date of Manufacture on Packaging

The date of manufacture on the toner cartridge box is intended for HP internal processes and may be required to comply with regulatory standards in certain countries. The date of manufacture is not an expiration or “use before” date. There is no expiration date for the use of HP toner cartridges.

https://support.hp.com/sg-en/document/c06457083