Phase 2 — Official Start Date and Details?

ARC White-Box Estimation Challenge 2026
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Hi organizers,

Could you please clarify the current status of Phase 2?

Phase 2 was originally expected to begin on August 18, and the challenge page now appears to indicate that Phase 2 is live. However, I haven’t seen an official Phase 2 launch announcement or a post outlining the Phase 2 rules and setup yet.

Could you please confirm:

When will Phase 2 officially begin / become available for submissions?

Does the challenge page showing Phase 2 as “live” mean that Phase 2 has already started, or is the actual launch still pending?

When can we expect the Phase 2 rules, constraints, evaluator/compute budget, dataset details, and any changes from Phase 1 to be announced?

Just wanted to clarify the timeline so that participants know when to start working under the Phase 2 setup.

Thanks!

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It’s live now, I just don’t think their social media people work on the weekends.

edit: Submissions are still closed: “:warning: Phase 1 is completed — submissions are closed.”

MLP shape is now 1024x16. So wider than phase 1, but shallower.

Dataset summary — v2-phase2
Splits mini, full
MLPs total 1100
mini split MLPs 100
full split MLPs 1,000
Width 1024
Depth 16
Monte Carlo samples per MLP (N) 1,000,000,000
Schema version 3.0
Seed protocol whestbench_explicit_per_mlp_seeds v3.0
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@jwaling_mehta : Heres the official announcement: Phase 2 of the ARC White-Box Estimation Challenge is live 🚀