{"id":"X11","title":"X11 License","reviewed_on":"2026-09-22","reviewer":"Giray Havur","text_source":"https://raw.githubusercontent.com/spdx/license-list-data/main/text/X11.txt","text_retrieved":true,"verdict":"created","summary":"Models the licence the X Consortium wrote for the X Window System. The grant and the notice condition are the MIT ones word for word; what the X text adds is a clause keeping the consortium's name out of advertising and promotion, and a sentence noting the trademark. The record is MIT plus a dalicc:promote prohibition.","findings":[{"rubric":1,"severity":"info","field":"spdx:licenseId","description":"File name, record identifier, SPDX identifier and IRI local name are all X11. SPDX keeps X11 and MIT as separate identifiers although the grant is the same, because of the name clause, and so does this library.","action":"applied"},{"rubric":2,"severity":"info","field":"odrl:target","description":"One odrl:AssetCollection of dct:type dcmitype:Software, following MIT.","action":"applied"},{"rubric":3,"severity":"major","field":"odrl:permission","description":"The grant reads \"Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the \"Software\"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so\". The record permits reproduce, distribute, modify, derive, display, present, grantUse, sublicense, commercial use, derivative works, modified works and the distribution fee.","action":"applied"},{"rubric":3,"severity":"major","field":"odrl:permission","description":"dalicc:ChangeLicense is permitted with the dalicc:compliantLicense duty, as on MIT.","action":"applied"},{"rubric":4,"severity":"major","field":"odrl:prohibition","description":"dalicc:promote is prohibited for \"Except as contained in this notice, the name of the X Consortium shall not be used in advertising or otherwise to promote the sale, use or other dealings in this Software without prior written authorization from the X Consortium\". This is the one statement that separates the record from MIT.","action":"applied"},{"rubric":5,"severity":"major","field":"odrl:duty","description":"cc:Attribution and cc:Notice hang off odrl:distribute, odrl:modify and odrl:derive for \"The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software\".","action":"applied"},{"rubric":6,"severity":"minor","field":"dalicc:WarrantyDisclaimer","description":"The disclaimer paragraph holds the warranty sentence and the liability sentence and is split into the two predicates, as on MIT-0.","action":"applied"},{"rubric":6,"severity":"info","field":"dalicc:additionalClauses","description":"The trademark sentence, \"X Window System is a trademark of X Consortium, Inc.\", is quoted. dalicc:trademarkNotice is not used: the sentence states a fact about a mark and puts no duty on the licensee, and the duty term is for a licence that asks the licensee to carry such a notice forward.","action":"applied"},{"rubric":7,"severity":"info","field":"cc:jurisdiction","description":"The text names no legal system and sets no term, so cc:jurisdiction is dalicc:worldwide and dalicc:validityType is dalicc:perpetual.","action":"applied"},{"rubric":8,"severity":"info","field":"dalicc:additionalClauses","description":"No clause of this text needs a term the vocabulary does not have.","action":"none"},{"rubric":9,"severity":"info","field":"record","description":"The consistency check of app.services.composer against the dependency graph dg_default returned an empty conflict list.","action":"none"},{"rubric":10,"severity":"info","field":"record","description":"Read against licensedata/licenses/MIT.ttl the difference is one prohibition, dalicc:promote, and two quoted clauses. The permission set is the MIT set with dalicc:sublicense stated as well, which MIT-0 also does for the same wording of the grant.","action":"none"}],"family":"Permissive variants","port_of":null,"variant_kind":null,"variant_of":null,"notes":"cc:legalcode and dct:source both point at the SPDX page. cc:attributionName and dct:publisher name the X Consortium, the body the text names as the copyright holder and the party whose permission the name clause requires."}