This dataset contains the labelled concepts used to generate the Concept Recognition results in "SpaceTransformers: Language Modeling for Space Systems" published by IEEE Access (10.1109/ACCESS.2021.3115659). In this paper, a novel family of domain-specific models, SpaceTransformers was further pre-trained from BERT, RoBERTa and SciBERT on unstructured data related to space systems. The models were then fine-tuned on a domain-specific Concept Recognition task. Additional Links: 1) The code is available at github.com/strath-ace/smart-nlp. 2) The further pre-training corpus is available at doi.org/10.15129/8e1c 3353-ccbe-4835-b4f9-bffd6b5e058b. 3) The ECSS requirements used as fine-tuning corpus can be accessed through https://ecss.nl/standards/downloads/doors-download/. If re-using this dataset, please do cite our work: @ARTICLE{9548078, author={Berquand, Audrey and Darm, Paul and Riccardi, Annalisa}, journal={IEEE Access}, title={SpaceTransformers: Language Modeling for Space Systems}, year={2021}, volume={9}, pages={133111-133122}, doi={10.1109/ACCESS.2021.3115659}}