The data-retention period for passive HF NFC tags is typically 10 years. Does anybody manufacture passive HF NFC tags with longer retention periods—and, if so, who is doing this?
To answer your question, I reached out to Richard Aufreiter, HID Global's director of product management for identification technologies. HID makes passive HF and UHF RFID transponders. Here is Richard's informed response (with some minor edits for clarity):
"Data retention is not a function of the tag, but of the chip (to be more precise, the chip's memory). Most chips are based on EEPROM, for which vendors typically specify ~100K write cycles and 10 years' lifetime. So the same NFC chip—e.g. NTAG 21x—will always have the same retention time, independent of which tag vendor is integrating the chip into a tag. The 10 years are typically guaranteed for the extremes of the operating temperature range. So, if the chip is used at room temperature for most of its lifetime, the retention rate is usually much longer. We have been in the business for 25 years, and I don't know of any failure due to memory aging."
I can also confirm that I have never heard of an RFID transponder losing its chip memory.
—Mark Roberti, Founder and Editor, RFID Journal