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+# MS MARCO License Terms
+
+The MS MARCO datasets were released by Microsoft in 2016 (initial release) and
+have been updated through several follow-on competitions and BEIR-style
+re-releases. They are distributed under a non-standard set of "MS MARCO" terms
+authored by Microsoft Research — not under a Creative Commons or open-source
+license — granting a non-exclusive, royalty-free right to use the dataset for
+non-commercial research purposes, with attribution.
+
+## What you can do
+
+- Use the dataset for research, experimentation, and benchmarking.
+- Train and evaluate models on it (passage retrievers, rerankers, generative
+  QA, embedding models).
+- Publish numbers against the standard MS MARCO splits (dev / eval / TREC
+  Deep Learning subsets) without separate clearance.
+- Redistribute the dataset in unmodified form for research use, with
+  attribution back to Microsoft.
+
+## What you should still do
+
+- **Attribute Microsoft** as the source whenever the dataset is used,
+  redistributed, or referenced — including paper citations, blog posts, and
+  downstream dataset cards.
+- **Treat commercial deployment as a separate question.** The release terms
+  are explicitly research-oriented. Productionising a model that was trained
+  on MS MARCO (or evaluating it as part of a paid product) is not addressed
+  by the dataset license and should be reviewed independently.
+- **Do not redistribute the held-out evaluation labels.** The TREC Deep
+  Learning evaluation qrels are released asynchronously and treating them
+  as part of the public corpus undermines the benchmark.
+- **Respect Bing's terms.** The passages are extracted from real Bing web
+  search results; redistributing the source URLs or attempting to re-crawl
+  the linked pages remains subject to Bing's and the linked sites'
+  individual terms.
+
+## Background
+
+- Original release: Bajaj, Nguyen, et al. — *MS MARCO: A Human Generated
+  Machine Reading Comprehension Dataset* (2016).
+- Project site:
+  [microsoft.github.io/msmarco/](https://microsoft.github.io/msmarco/)
+- Passage retrieval task overview:
+  [microsoft.github.io/msmarco/Datasets#passage-ranking-dataset](https://microsoft.github.io/msmarco/Datasets#passage-ranking-dataset)
+
+## SPDX identifier
+
+No formal SPDX identifier is registered. Catalogued here as
+`ms-marco-terms`.