Clarify upstream license status and private access

README.md

@@ -71,4 +71,4 @@ The paper reports a mean over **10 inference runs**. To obtain comparable *run c
 
 ## Source and redistribution
 
-This subset's records match the `trl-lib/math_shepherd` test split, which attributes its processed format to the [Math-Shepherd project](https://huggingface.co/datasets/peiyi9979/Math-Shepherd). See the original dataset and paper for citations. The upstream TRL dataset card does not state a license; **confirm the applicable data terms before making a new public repository**. This dataset card does not assign a new license to third-party data.
+This subset's records match the [`trl-lib/math_shepherd` test split](https://huggingface.co/datasets/trl-lib/math_shepherd), which attributes its processed format to the [original Math-Shepherd project](https://huggingface.co/datasets/peiyi9979/Math-Shepherd). See the original dataset and paper for citations. Neither of those two dataset cards states a data license. This repository remains **private until the applicable redistribution terms are confirmed**; this card does not assign a new license to third-party data.