This dataset compiles experimentally validated splice leader (SL) sequences from diverse eukaryotic taxa, providing a comparative reference for studies on trans-splicing and RNA processing. Version 7 represents a major update from v3 (January 2025), nearly doubling the number of entries from 112 to 210 sequences (+98 entries, +87%).Taxonomic coverage has been significantly expanded to now include 11 phyla: Euglenozoa, Nematoda, Platyhelminthes, Cnidaria, Rotifera, Chordata, Alveolata, and four newly added phyla — Arthropoda (Copepoda), Chaetognatha (Sagittoidea), Cryptista (Cryptomonada), and Ctenophora (Tentaculata/Nuda). The largest expansions were in Nematoda, Cnidaria, and Chaetognatha.The dataset schema was restructured to improve phylogenetic resolution, replacing the single "Family" field with a two-level "Phylum / Subgroup" classification. A formal SL sequence naming convention was introduced, with 170 of 210 entries carrying standardized identifiers. Each entry includes the SL sequence (5' to 3'), sequence length, primary literature reference (DOI and PMID), and contributor information.

This dataset compiles experimentally validated splice leader (SL) sequences from diverse eukaryotic taxa, providing a comparative reference for studies on trans-splicing and RNA processing. Version 7 represents a major update from v3 (January 2025), nearly doubling the number of entries from 112 to 210 sequences (+98 entries, +87%).Taxonomic coverage has been significantly expanded to now include 11 phyla: Euglenozoa, Nematoda, Platyhelminthes, Cnidaria, Rotifera, Chordata, Alveolata, and four newly added phyla — Arthropoda (Copepoda), Chaetognatha (Sagittoidea), Cryptista (Cryptomonada), and Ctenophora (Tentaculata/Nuda). The largest expansions were in Nematoda, Cnidaria, and Chaetognatha.The dataset schema was restructured to improve phylogenetic resolution, replacing the single "Family" field with a two-level "Phylum / Subgroup" classification. A formal SL sequence naming convention was introduced, with 170 of 210 entries carrying standardized identifiers. Each entry includes the SL sequence (5' to 3'), sequence length, primary literature reference (DOI and PMID), and contributor information.