This developer's guide to the libSBML API does not provide a complete explanation of SBML itself. If you are developing SBML software, you are strongly urged to read the actual SBML specifications.

SBML specifications, current at the time of this libSBML release.
Note: an Internet connection is required to access these documents.
SBML core specifications
Specification (in PDF format)	Known issues	Special notes
SBML Level 3 Version 2 Core (Release 1)	Errata page
SBML Level 3 Version 1 Core (Release 2)	Errata page
SBML Level 2 Version 5 (Release 1)	Errata page
SBML Level 2 Version 4 (Release 1)	Errata page
SBML Level 2 Version 3 (Release 2)	Errata page
SBML Level 2 Version 2 (Release 1)	Errata page
SBML Level 2 Version 1 (Release 1)	Errata page	Has significant limitations; use later L2 versions instead.
SBML Level 1 Version 2 (Release 1)	Errata page
SBML Level 1 Version 1 (Release 1)	(No errata list)	Obsolete; do not use for new models.
SBML package specifications
Specification (in PDF format)	Known issues	Special notes
Flux Balance Constraints, version 1	Errata page	See the activity page for 'fbc' for more information
Flux Balance Constraints, version 2	Errata page	See the activity page for 'fbc' for more information
Groups	Errata page	See the activity page for 'groups' for more information
Hierarchical Model Composition	Errata page	See the activity page for 'comp' for more information
Layout	Errata page	See the activity page for 'layout' for more information
Render	Errata page	See the activity page for 'render' for more information
Multistate, Multicomponent and Multicompartment Species	Errata page	See the activity page for 'multi' for more information
Qualitative Models	Errata page	See the activity page for 'qual' for more information