RESO RETS deprecated June 2018; DD 2.0 ratified Oct 23 2023, effective April 15 2024; NAR-affiliated MLS one-year certification (industry-reported ~April 2025)

Claim. RESO deprecated/stopped supporting RETS in June 2018. DD 2.0 was ratified October 23, 2023 with an effective ratification date of April 15, 2024 for certification testing. Industry sources (WAV Group; repeated by Constellation/MEV) report NAR-affiliated MLSs had to certify on DD 2.0 within one year (~April 2025).

Source. reso.org; reso.org/product-updates; WAV Group via mlsimport.com vendor blog, accessed 2026-06-21.

Confidence. Verified for the RETS deprecation date and DD 2.0 ratification dates (RESO primary). Industry-reported / single-source for the NAR one-year mandate — the WAV Group framing is not confirmed on a RESO or NAR primary page.

Caveats. The NAR one-year mandate is the only piece without a primary source in the trail; treat as industry-reported, not RESO-primary-confirmed.

Implication / use. Standards timeline anchor. The 2018 RETS sunset matters for any "we built this on RETS" legacy claim; the 2024 DD 2.0 effective date matters for any "we conform to DD 2.0" data-product claim.