Thanks for using the forum.
It may be dependent on the manufacturer. As far as I know the syringe itself will not expire, but the rubber stopper on the syringe plunger may have a shelf life. If you have a bunch of syringes that are due to expire, I would recommend speaking with the manufacturer, they may be able to give you some insight on why the syringe has an expiration date.
I hope this helps.
The problem is not with the syringe, needle, stopper plunger ect. The syringe was sealed in the plastic envelope and then either gassed , steamed or irradiated to ensure it was sterile just after manufacture. Then it sat on several shelves waiting to be sold (hold time) the problem is that the manufacturer cannot guarantee the sterility of the whole package past a certain date because the effects of temperature, humidity during hold time and mechanical vibration during transportation all reduce the effectiveness of the package seal at keeping bacteria out. If one syringe from a batch was found to be contaminated in for example a pharmacy the company may have to recall the whole batch hence the short shelf life and added expense.