Summary (200 words): This report outlines updated Earth BioGenome Project (EBP) assembly standards (Revision 7, 2025), reflecting advances in sequencing and assembly technologies. It defines quantitative targets for high-quality genomes, primarily 6.C.Q40 (megabase contiguity, chromosome-scale scaffolds, and ≤1 error per 10,000 bases), alongside ≥90% completeness metrics (k-mers, BUSCO genes, chromosomal assignment) and low duplication rates.

Three organism categories are addressed:

Standard eukaryotes with sufficient DNA: Target 6.C.Q40; telomere-to-telomere (T2T, Q60) assemblies are emerging but not yet routine.

Low-input species: Reduced standards (e.g. 5.C.Q40 or 5.6.Q40) due to amplification limitations.

Unculturable single-cell eukaryotes: Standards still under development.

Additional requirements include removing contamination, separating organellar and haplotypic sequences, ensuring clean sequence formatting, and performing curation (e.g. correcting misassemblies, naming chromosomes, validating against karyotypes). Submission to INSDC with raw data and structured BioProjects is mandatory.

Diploid assemblies should ideally include phased haplotypes (e.g. hap1/hap2 or maternal/paternal), with the primary reference representing a complete haploid genome including sex chromosomes.

The document emphasizes continuous improvement, encouraging data sharing and anticipating reduced costs and increasing feasibility of high-quality assemblies across diverse species.