Which is reported here: https://classic.mceliece.org/iso.html

From the Classic McEliece pages:
“ISO standardized Classic McEliece in June 2026. The ISO standard is compatible with the official specification from the Classic McEliece team.”

The actual standard by ISO can be found here (behind a paywall):
https://www.iso.org/obp/ui/en/#iso:std:iso-iec:18033:-2:ed-1:v1:amd:2:v1:en

An article with more information by TU Eindhoven (NL) on the contribution by professor Tanja Lange can be found here:
https://www.tue.nl/en/news-and-events/news-overview/26-06-2026-professor-tanja-lange-and-team-contribute-to-new-global-standard-for-post-quantum-cryptography

Businesswire also reports this development here:
https://www.businesswire.com/news/home/20260715570640/en/Post-Quantums-Algorithm—Classic-McEliece—Achieves-Global-ISO-Standardization-to-Protect-the-World-From-Quantum-Cyber-Attack