diff --git a/licenses/README.md b/licenses/README.md
index 5a83c86..1c3d66e 100644
--- a/licenses/README.md
+++ b/licenses/README.md
@@ -2,35 +2,44 @@
 
 The following table provides the licenses for resources contributing nodes or edges to the network. `Source` indicates the date when and location where the license information was retrieved. Blank values indicate no licensing information was found. `Institution` indicates where the resource was created. `Funder` indicates who funded the project and links to the source of the funding information.
 
-| Resource | License | Source | Institution | Funder |
-| -------- | ------- | ------ | ----------- | ------- |
-| Disease Ontology | [CC BY 3.0](https://creativecommons.org/licenses/by/3.0/) |  [2015-08-20](http://disease-ontology.org/resources/) | University of Maryland | [NIH, EMBL, DOE](https://doi.org/10.1093/nar/gku1011) |
-| DrugBank 4.2 | [custom](custom/DrugBank.md) | [2015-08-20](http://www.drugbank.ca/) | University of Alberta | [CIHR, AIHS, TIMC](http://www.drugbank.ca/about) |
-| Entrez Gene | [custom](custom/NCBI.md) | [2015-08-31](http://www.ncbi.nlm.nih.gov/home/about/policies.shtml) |  NCBI | USFG |
-| Uberon | [CC BY 3.0](http://creativecommons.org/licenses/by/3.0/) | [2015-08-30](https://github.com/obophenotype/uberon/issues/1139#issuecomment-136204582) | LBNL, OHSU | [NIH, NSF](http://obofoundry.org/ontology/uberon.html) |
-| MeSH | [custom](custom/MeSH.md) | [2015-08-21](https://www.nlm.nih.gov/mesh/termscon.html) | NCBI | USFG |
-| WikiPathways | [CC BY 3.0](https://creativecommons.org/licenses/by/3.0/) / [custom](custom/WikiPathways.md) | [2015-08-20](http://www.wikipathways.org/index.php/WikiPathways:License_Terms) |  Gladstone Institutes, Maastricht University | [NIH](http://grantome.com/grant/NIH/R01-GM100039-04) |
-| MSigDB | [custom](custom/MSigDB.asciidoc) | [2015-08-20](http://www.broadinstitute.org/gsea/msigdb/download_file.jsp?filePath=/resources/licenses/gsea_msigdb_license.txt) | Broad Institute | [NIH](http://grantome.com/grant/NIH/R01-CA121941-09) |
-| Gene Ontology | [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/legalcode) | [2015-08-21](http://geneontology.org/page/use-and-license) | Gene Ontology Consortium | [NHGRI](http://geneontology.org/faq/who-funds-go) |
-| GWAS Catalog | [custom](custom/EBI.md) | [2015-09-17](http://www.ebi.ac.uk/about/terms-of-use) | EBI | [NHGRI](https://www.ebi.ac.uk/gwas/docs/about) |
-| DOAF |  |  | Northwestern University| [NIH](https://doi.org/10.1371/journal.pone.0049686) |
-| DISEASES | [CC BY 4.0](http://creativecommons.org/licenses/by/4.0/) | [2015-08-21](http://diseases.jensenlab.org/Downloads) | University of Copenhagen | [Novo Nordisk Foundation Center, EU's FP7](https://doi.org/10.1016/j.ymeth.2014.11.020) |
-| DisGeNET | [ODbL](http://opendatacommons.org/licenses/odbl/) |  [2015-08-21](http://www.disgenet.org/web/DisGeNET/menu) | Universitat Pompeu Fabra | [ISCIII, IMI, EU's FP7, EFPIA](https:doi.org/10.1093/database/bav028) |
-| ADEPTUS |  |  | Tel Aviv University | [Israel Science Foundation, Azrieli Foundation, I-CORE](https://doi.org/10.1093/nar/gkv810) |
-| STARGEO |  |  | UCSF | |
-| MEDLINE | [custom](custom/MEDLINE.md) | [2015-08-21](http://www.nlm.nih.gov/databases/journal.html) | NLM | USFG |
-| Bgee | | | University of Lausanne & Swiss Institute of Bioinformatics |  [Etat de Vaud, SIB](https://doi.org/10.1007/978-3-540-69828-9_12) |
-| TISSUES | [CC BY 4.0](http://creativecommons.org/licenses/by/4.0/) | [2015-08-21](http://tissues.jensenlab.org/Downloads) | University of Copenhagen | [Novo Nordisk Foundation, NIH, CSIRO](https://doi.org/10.7717/peerj.1054) |
-| BindingDB | [mixed](custom/BingindDB.md) CC BY 3.0 & CC BY-SA 3.0 | [2015-08-21](https://www.bindingdb.org/bind/info.jsp) | BindingDB | [NIH](http://grantome.com/grant/NIH/R01-GM070064-12) |
-| hetio-dag |  |  | UCSF | NSF |
-| Human Interactome Database |  |  | Harvard CCSB | [NHGRI, NCI, NSF, DFCI, Ellison Foundation, W. M. Keck Foundation](http://interactome.dfci.harvard.edu/)
-| Incomplete Interactome |  |  | Northeastern University, DFCI | [NIH, NHGRI, NHLBI](https://doi.org/10.1126/science.1257601) |
-| Evolutionary Rate Covariation |  |  | University of Pittsburgh | [Pittsburgh Foundation, PA Department of Health, NIH, NSF](https://doi.org/10.1371/journal.pgen.1004967) |
-| MEDI | [CC BY-NC-SA 3.0](http://creativecommons.org/licenses/by-nc-sa/3.0/deed.en_US) | [2015-08-21](http://knowledgemap.mc.vanderbilt.edu/research/content/MEDI) | Vanderbilt University | [NIH](https://doi.org/10.1136/amiajnl-2012-001431) |
-| ehrlink |  |  | UTHealth | [ONC SHARP, NIH](https://doi.org/10.1136/amiajnl-2012-000852) |
-| LabeledIn | [custom](custom/LabeledIn.txt) | [2015-08-21](http://ftp.ncbi.nlm.nih.gov/pub/lu/LabeledIn/README.txt) | NCBI | USFG |
-| PREDICT | [CC BY-NC-SA 3.0](http://creativecommons.org/licenses/by-nc-sa/3.0/) | [2015-08-21](http://msb.embopress.org/content/7/1/496) | Tel‐Aviv University | [Israel Science Foundation](https://doi.org/10.1038/msb.2011.26) |
-| LINCS L1000 | [custom](custom/L1000.md) | [2015-10-16](http://www.lincscloud.org/license/) | Broad Institute | NIH |
-| SIDER 4 | [CC BY-NC-SA 4.0](http://creativecommons.org/licenses/by-nc-sa/4.0/) | [2015-08-21](http://sideeffects.embl.de/download/) | EMBL | [Novo Nordisk Foundation, EMBL](https://doi.org/10.1093/nar/gkv1075) |
+Resources are classified into four categories (denoted by ∈):
 
-This table was manually compiled by @dhimmel and may contain inaccuracies or omissions.
+1. Resources that are in the **public domain**.
+2. Resources with a license that **allows** use, redistribution, and modification.
+3. Resources with a license that **forbids** use, redistribution, or modification.
+4. Resources that **do not have** a license.
+
+The table is sorted by category, then license leniency, then alphabetical order.
+
+| ∈ | Resource | License | Source | Institution | Funder |
+| --- | -------- | ------- | ------ | ----------- | ------ |
+| 1 | Entrez Gene | [custom](custom/NCBI.md) | [2015-08-31](http://www.ncbi.nlm.nih.gov/home/about/policies.shtml) |  NCBI | USFG |
+| 1 | MEDLINE | [custom](custom/MEDLINE.md) | [2015-08-21](http://www.nlm.nih.gov/databases/journal.html) | NLM | USFG |
+| 1 | LabeledIn | [custom](custom/LabeledIn.txt) | [2015-08-21](http://ftp.ncbi.nlm.nih.gov/pub/lu/LabeledIn/README.txt) | NCBI | USFG |
+| 1 | MeSH | [custom](custom/MeSH.md) | [2015-08-21](https://www.nlm.nih.gov/mesh/termscon.html) | NCBI | USFG |
+| 2 | Disease Ontology | [CC BY 3.0](https://creativecommons.org/licenses/by/3.0/) |  [2015-08-20](http://disease-ontology.org/resources/) | University of Maryland | [NIH, EMBL, DOE](https://doi.org/10.1093/nar/gku1011) |
+| 2 | DISEASES | [CC BY 4.0](http://creativecommons.org/licenses/by/4.0/) | [2015-08-21](http://diseases.jensenlab.org/Downloads) | University of Copenhagen | [Novo Nordisk Foundation Center, EU's FP7](https://doi.org/10.1016/j.ymeth.2014.11.020) |
+| 2 | Gene Ontology | [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/legalcode) | [2015-08-21](http://geneontology.org/page/use-and-license) | Gene Ontology Consortium | [NHGRI](http://geneontology.org/faq/who-funds-go) |
+| 2 | GWAS Catalog | [custom](custom/EBI.md) | [2015-09-17](http://www.ebi.ac.uk/about/terms-of-use) | EBI | [NHGRI](https://www.ebi.ac.uk/gwas/docs/about) |
+| 2 | LINCS L1000 | [custom](custom/L1000.md) | [2015-10-16](http://www.lincscloud.org/license/) | Broad Institute | NIH |
+| 2 | TISSUES | [CC BY 4.0](http://creativecommons.org/licenses/by/4.0/) | [2015-08-21](http://tissues.jensenlab.org/Downloads) | University of Copenhagen | [Novo Nordisk Foundation, NIH, CSIRO](https://doi.org/10.7717/peerj.1054) |
+| 2 | Uberon | [CC BY 3.0](http://creativecommons.org/licenses/by/3.0/) | [2015-08-30](https://github.com/obophenotype/uberon/issues/1139#issuecomment-136204582) | LBNL, OHSU | [NIH, NSF](http://obofoundry.org/ontology/uberon.html) |
+| 2 | WikiPathways | [CC BY 3.0](https://creativecommons.org/licenses/by/3.0/) / [custom](custom/WikiPathways.md) | [2015-08-20](http://www.wikipathways.org/index.php/WikiPathways:License_Terms) |  Gladstone Institutes, Maastricht University | [NIH](http://grantome.com/grant/NIH/R01-GM100039-04) |
+| 2 | BindingDB | [mixed](custom/BingindDB.md) CC BY 3.0 & CC BY-SA 3.0 | [2015-08-21](https://www.bindingdb.org/bind/info.jsp) | BindingDB | [NIH](http://grantome.com/grant/NIH/R01-GM070064-12) |
+| 2 | DisGeNET | [ODbL](http://opendatacommons.org/licenses/odbl/) |  [2015-08-21](http://www.disgenet.org/web/DisGeNET/menu) | Universitat Pompeu Fabra | [ISCIII, IMI, EU's FP7, EFPIA](https:doi.org/10.1093/database/bav028) |
+| 2 | DrugBank 4.2 | [custom](custom/DrugBank.md) | [2015-08-20](http://www.drugbank.ca/) | University of Alberta | [CIHR, AIHS, TIMC](http://www.drugbank.ca/about) |
+| 2 | MEDI | [CC BY-NC-SA 3.0](http://creativecommons.org/licenses/by-nc-sa/3.0/deed.en_US) | [2015-08-21](http://knowledgemap.mc.vanderbilt.edu/research/content/MEDI) | Vanderbilt University | [NIH](https://doi.org/10.1136/amiajnl-2012-001431) |
+| 2 | PREDICT | [CC BY-NC-SA 3.0](http://creativecommons.org/licenses/by-nc-sa/3.0/) | [2015-08-21](http://msb.embopress.org/content/7/1/496) | Tel‐Aviv University | [Israel Science Foundation](https://doi.org/10.1038/msb.2011.26) |
+| 2 | SIDER 4 | [CC BY-NC-SA 4.0](http://creativecommons.org/licenses/by-nc-sa/4.0/) | [2015-08-21](http://sideeffects.embl.de/download/) | EMBL | [Novo Nordisk Foundation, EMBL](https://doi.org/10.1093/nar/gkv1075) |
+| 3 | MSigDB | [custom](custom/MSigDB.asciidoc) | [2015-08-20](http://www.broadinstitute.org/gsea/msigdb/download_file.jsp?filePath=/resources/licenses/gsea_msigdb_license.txt) | Broad Institute | [NIH](http://grantome.com/grant/NIH/R01-CA121941-09) |
+| 4 | ADEPTUS |  |  | Tel Aviv University | [Israel Science Foundation, Azrieli Foundation, I-CORE](https://doi.org/10.1093/nar/gkv810) |
+| 4 | Bgee | | | University of Lausanne & Swiss Institute of Bioinformatics |  [Etat de Vaud, SIB](https://doi.org/10.1007/978-3-540-69828-9_12) |
+| 4 | DOAF |  |  | Northwestern University| [NIH](https://doi.org/10.1371/journal.pone.0049686) |
+| 4 | ehrlink |  |  | UTHealth | [ONC SHARP, NIH](https://doi.org/10.1136/amiajnl-2012-000852) |
+| 4 | Evolutionary Rate Covariation |  |  | University of Pittsburgh | [Pittsburgh Foundation, PA Department of Health, NIH, NSF](https://doi.org/10.1371/journal.pgen.1004967) |
+| 4 | hetio-dag |  |  | UCSF | NSF |
+| 4 | Incomplete Interactome |  |  | Northeastern University, DFCI | [NIH, NHGRI, NHLBI](https://doi.org/10.1126/science.1257601) |
+| 4 | Human Interactome Database |  |  | Harvard CCSB | [NHGRI, NCI, NSF, DFCI, Ellison Foundation, W. M. Keck Foundation](http://interactome.dfci.harvard.edu/) |
+| 4 | STARGEO |  |  | UCSF |  |
+
+This table was manually compiled by [@dhimmel](https://github.com/dhimmel "dhimmel on GitHub") and may contain inaccuracies or omissions. See the [corresponding _Thinklab_ discussion](https://doi.org/10.15363/thinklab.d107 "Integrating resources with disparate licensing into an open network") for more information on the legal issues surrounding our data integration.