Cascading Style Sheets (CSS) Working Group - IPR

Licensing Commitments

Participants in this group have made certain licensing commitments by joining the group. In addition to these Participants, non-participating W3C Member may have made licensing commitments.

W3C Members not participating in this group who wish to make the same licensing commitments for specifications developed by this group may do so through a Join form for licensing commitments from non-participating Members.

Other parties making a substantive contribution to the work of the group need to make a Royalty-Free patent commitment, as described in section 6.2.6 of the Process. Team contacts will provide instructions for recording the non-participant licensing commitment before the contribution can be accepted.

Participation

W3C Member Organizations
  • 360
  • Adobe
  • Alibaba Group
  • Amazon
  • Apple Inc.
  • Baidu, Inc.
  • BFO
  • Bloomberg
  • Bocoup
  • British Broadcasting Corporation
  • ByteDance
  • Electronics and Telecommunications Research Institute (ETRI)
  • eyeo GmbH
  • Google LLC
  • IBM Corporation
  • Igalia
  • Intel Corporation
  • Kodansha, Publishers, Ltd.
  • LG Electronics
  • LSEG
  • Microsoft Corporation
  • Ministry of Digital Affairs, Taiwan
  • MITRE Corporation
  • Monotype
  • MovieLabs
  • Mozilla Foundation
  • Navy Federal Credit Union
  • Rakuten Group, Inc.
  • Salesforce
  • Samsung Electronics Co., Ltd.
  • Shopify
  • Skynet Technologies
  • Tencent
  • TetraLogical Services Ltd
  • The New York Times
  • Thomson Reuters Corp.
  • TPGi
  • Wix.com Ltd.

Note: Log in to see links to organizations if you have member access

Invited Experts
  • Brian Birtles
  • Amy Carney
  • Hidde de Vries
  • Dael Jackson
  • Brad Kemper
  • Jirka Kosek
  • Vladimir Levantovsky
  • Peter Linss
  • Romain Menke
  • Jonathan Neal
  • François Remy
  • Florian Rivoal
  • Miriam Suzanne
  • Lea Verou
  • Sebastian Zartner
Team members
  • Richard Ishida
  • Chris Lilley
  • Michael[tm] Smith
  • Fuqiao Xue

See also the list of individuals participating in this group.

The Call for Participation for this group was announced on 2023-01-12; see the Patent Policy FAQ for information about continued participation before re-joining the group.

Specifications published by the Group

The following is the list of specifications produced by the Cascading Style Sheets (CSS) Working Group that have associated disclosures obligations, and possible licensing obligations under the W3C Patent Policy.

Document under the W3C Patent Policy Patent Disclosure Patent Exclusion
CSS Namespaces Module Level 3 disclose exclude
Cascading Style Sheets Level 2 Revision 1 (CSS 2.1) Specification disclose exclude
Cascading Style Sheets, level 1 disclose exclude
Selectors Level 3 disclose exclude
CSS Cascading and Inheritance Level 3 disclose exclude
CSS Multi-column Layout Module Level 1 disclose exclude
CSS Values and Units Module Level 3 disclose exclude
Media Queries Level 3 disclose exclude
CSS Style Attributes disclose exclude
CSS Backgrounds and Borders Module Level 3 disclose exclude
CSS3 module: Border disclose exclude
CSS Box Model Module Level 3 disclose exclude
CSS Fonts Module Level 3 disclose exclude
CSS3 module: line disclose exclude
CSS Lists and Counters Module Level 3 disclose exclude
CSS Ruby Annotation Layout Module Level 1 disclose exclude
CSS Basic User Interface Module Level 3 (CSS3 UI) disclose exclude
CSS Color Module Level 3 disclose exclude
CSS Text Module Level 3 disclose exclude
CSS Generated Content Module Level 3 disclose exclude
CSS Paged Media Module Level 3 disclose exclude
CSS Speech Module Level 1 disclose exclude
CSS Syntax Module Level 3 disclose exclude
SVG's XML Binding Language (sXBL) disclose exclude
CSS Generated Content for Paged Media Module disclose exclude
CSS Grid Positioning Module Level 3 disclose exclude
CSSOM View Module disclose exclude
CSS 2D Transforms disclose exclude
CSS 3D Transforms Module Level 3 disclose exclude
CSS Animations Level 1 disclose exclude
CSS Flexible Box Layout Module Level 1 disclose exclude
CSS Images Module Level 3 disclose exclude
CSS Transitions disclose exclude
CSS Writing Modes Level 3 disclose exclude
CSS Device Adaptation Module Level 1 disclose exclude
CSS Conditional Rules Module Level 3 disclose exclude
CSS Exclusions Module Level 1 disclose exclude
CSS Grid Layout Module Level 1 disclose exclude
CSS Regions Module Level 1 disclose exclude
CSS Object Model (CSSOM) disclose exclude
Selectors Level 4 disclose exclude
Compositing and Blending Level 1 disclose exclude
CSS Counter Styles Level 3 disclose exclude
CSS Masking Module Level 1 disclose exclude
CSS Text Decoration Module Level 3 disclose exclude
CSS Custom Properties for Cascading Variables Module Level 1 disclose exclude
CSS Box Alignment Module Level 3 disclose exclude
CSS Fragmentation Module Level 3 disclose exclude
CSS Positioned Layout Module Level 3 disclose exclude
CSS Box Sizing Module Level 3 disclose exclude
CSS Transforms Module Level 1 disclose exclude
CSS Images Module Level 4 disclose exclude
CSS Overflow Module Level 3 disclose exclude
Filter Effects Module Level 1 disclose exclude
CSS Shapes Module Level 1 disclose exclude
Web Animations disclose exclude
CSS Display Module Level 3 disclose exclude
CSS Font Loading Module Level 3 disclose exclude
CSS Line Grid Module Level 1 disclose exclude
CSS Scoping Module Level 1 disclose exclude
CSS Will Change Module Level 1 disclose exclude
Geometry Interfaces Module Level 1 disclose exclude
Media Queries Level 4 disclose exclude
CSS Inline Layout Module Level 3 disclose exclude
CSS Pseudo-Elements Module Level 4 disclose exclude
CSS Scroll Snap Module Level 1 disclose exclude
Motion Path Module Level 1 disclose exclude
CSS Cascading and Inheritance Level 4 disclose exclude
CSS Page Floats disclose exclude
CSS Round Display Level 1 disclose exclude
CSS Text Module Level 4 disclose exclude
CSS Basic User Interface Module Level 4 disclose exclude
Cascading Style Sheets Level 2 Revision 2 (CSS 2.2) Specification disclose exclude
CSS Painting API Level 1 disclose exclude
CSS Properties and Values API Level 1 disclose exclude
CSS Typed OM Level 1 disclose exclude
CSS Color Module Level 4 disclose exclude
CSS Table Module Level 3 disclose exclude
CSS Easing Functions Level 1 disclose exclude
CSS Containment Module Level 1 disclose exclude
CSS Rhythmic Sizing disclose exclude
CSS Fill and Stroke Module Level 3 disclose exclude
CSS Logical Properties and Values Level 1 disclose exclude
CSS Overflow Module Level 4 disclose exclude
CSS Fonts Module Level 4 disclose exclude
CSS Writing Modes Level 4 disclose exclude
CSS Grid Layout Module Level 2 disclose exclude
CSS Text Decoration Module Level 4 disclose exclude
CSS Layout API Level 1 disclose exclude
CSS Values and Units Module Level 4 disclose exclude
CSS Scrollbars Styling Module Level 1 disclose exclude
CSS Shadow Parts disclose exclude
CSS Fragmentation Module Level 4 disclose exclude
CSS Spatial Navigation Level 1 disclose exclude
CSS Color Adjustment Module Level 1 disclose exclude
CSS Overscroll Behavior Module Level 1 disclose exclude
CSS Animation Worklet API disclose exclude
CSS Containment Module Level 2 disclose exclude
Resize Observer disclose exclude
CSS Scroll Anchoring Module Level 1 disclose exclude
CSS Color Module Level 5 disclose exclude
Media Queries Level 5 disclose exclude
CSS Transforms Module Level 2 disclose exclude
CSS Conditional Rules Module Level 4 disclose exclude
CSS Box Model Module Level 4 disclose exclude
CSS Box Sizing Module Level 4 disclose exclude
CSS Custom Highlight API Module Level 1 disclose exclude
CSS Cascading and Inheritance Level 5 disclose exclude
CSS Fonts Module Level 5 disclose exclude
CSS Nesting Module disclose exclude
CSS Containment Module Level 3 disclose exclude
CSS Cascading and Inheritance Level 6 disclose exclude
CSS Conditional Rules Module Level 5 disclose exclude
CSS View Transitions Module Level 1 disclose exclude
Scroll-driven Animations disclose exclude
Web Animations Level 2 disclose exclude
CSS Animations Level 2 disclose exclude
CSS Anchor Positioning disclose exclude
CSS Transitions Level 2 disclose exclude
CSS Viewport Module Level 1 disclose exclude
Document not/no longer under the W3C Patent Policy Patent Disclosure Patent Exclusion
List of suggested extensions to CSS disclose Exclusion is not possible (document not under PP)
Aural Cascading Style Sheets (ACSS) Specification disclose Exclusion is not possible (document not under PP)
Behavioral Extensions to CSS disclose Exclusion is not possible (document not under PP)
Positioning HTML Elements with Cascading Style Sheets disclose Exclusion is not possible (document not under PP)
CSS3 introduction disclose Exclusion is not possible (document not under PP)
CSS Mobile Profile 2.0 disclose Exclusion is not possible (document not under PP)
CSS TV Profile 1.0 disclose Exclusion is not possible (document not under PP)
User Interface for CSS3 disclose Exclusion is not possible (document not under PP)
CSS Print Profile disclose Exclusion is not possible (document not under PP)
CSS Presentation Levels Module disclose Exclusion is not possible (document not under PP)
CSS3 Hyperlink Presentation Module disclose Exclusion is not possible (document not under PP)
The CSS ‘Reader’ Media Type disclose Exclusion is not possible (document not under PP)
CSS Template Layout Module disclose Exclusion is not possible (document not under PP)
Cascading Style Sheets (CSS) Snapshot 2007 disclose Exclusion is not possible (document not under PP)
CSS Marquee Module Level 3 disclose Exclusion is not possible (document not under PP)
Requirements for Japanese Text Layout 日本語組版処理の要件(日本語版) disclose Exclusion is not possible (document not under PP)
Cascading Style Sheets (CSS) Snapshot 2010 disclose Exclusion is not possible (document not under PP)
Fullscreen disclose Exclusion is not possible (document not under PP)
DOMMatrix interface disclose Exclusion is not possible (document not under PP)
Non-element Selectors Module Level 1 disclose Exclusion is not possible (document not under PP)
CSS Snapshot 2015 disclose Exclusion is not possible (document not under PP)
Worklets Level 1 disclose Exclusion is not possible (document not under PP)
CSS Snapshot 2017 disclose Exclusion is not possible (document not under PP)
CSS Snapshot 2018 disclose Exclusion is not possible (document not under PP)
CSS Snapshot 2020 disclose Exclusion is not possible (document not under PP)
CSS Snapshot 2021 disclose Exclusion is not possible (document not under PP)
CSS Snapshot 2022 disclose Exclusion is not possible (document not under PP)
CSS Snapshot 2023 disclose Exclusion is not possible (document not under PP)

Patent Disclosures and Claim Exclusions

This section summarizes patent disclosures by participants in W3C's Cascading Style Sheets (CSS) Working Group as required by section 6 of the W3C Patent Policy.

W3C takes no position regarding either:

  • the validity or scope of any intellectual property right or other rights that might be claimed to pertain to the implementation or use of the technology, or
  • the extent to which any license under such rights might or might not be available from those not participating in this group.

Where disclosure is required by a W3C Member, the AC Representative makes the disclosure.

Anyone else may also make a disclosure.

Known Disclosures

Disclosures made of claims believed to be essential for the implementation of CSS Mobile Profile 2.0
Disclosures for CSS Mobile Profile 2.0 Licensing Notes
Issued patent '6209009' (US) held by Openwave Systems Inc. disclosed on 2006-11-28
Disclosures made of claims believed to be essential for the implementation of CSS 2D Transforms
Disclosures for CSS 2D Transforms Licensing Notes
Laid-open/published patent application #12/397,325 (US) held by Apple Inc. disclosed on 2009-09-24 Patent Policy Obligations
Disclosures made of claims believed to be essential for the implementation of CSS 3D Transforms Module Level 3
Disclosures for CSS 3D Transforms Module Level 3 Licensing Notes
Laid-open/published patent application #12/397,325 (US) held by Apple Inc. disclosed on 2009-09-24 Patent Policy Obligations
Disclosures made of claims believed to be essential for the implementation of CSS Animations Level 1
Disclosures for CSS Animations Level 1 Licensing Notes
Laid-open/published patent application #12/397,325 (US) held by Apple Inc. disclosed on 2009-09-24 Patent Policy Obligations
Disclosures made of claims believed to be essential for the implementation of CSS Transitions
Disclosures for CSS Transitions Licensing Notes
Laid-open/published patent application #12/397,325 (US) held by Apple Inc. disclosed on 2009-09-24 Patent Policy Obligations

How to Make a Patent Disclosure

W3C Members and Invited Experts (including those not participating in this group) wishing to disclose a patent for any specification produced by the Cascading Style Sheets (CSS) Working Group should use the Cascading Style Sheets (CSS) Working Group patent disclosure form.

Disclosures from the general public should be sent to the W3C Staff.

For specifications developed under the W3C Patent Policy, parties that commit to the W3C Royalty-Free Licensing Terms are not required to disclose patents. Any party (not just the Working Group Participants) may commit to the W3C Royalty-Free Licensing Terms and may do so by following the instructions in the next section.

Claim Exclusions

Only Cascading Style Sheets (CSS) Working Group participants may exclude patent claims concerning specifications developed under the W3C Patent Policy, per section 4 of the W3C Patent Policy. To make an exclusion, participants should use the Cascading Style Sheets (CSS) Working Group patent claim exclusion form, but only after first disclosing the patent.

Exclusion Opportunities

The Patent Policy FAQ provides detailed information about exclusion opportunities, that is, when a Working Group Participant can exclude a patent claim.

Each exclusion opportunity has a duration. See section 4.1 of the W3C Patent Policy for information on how the exclusion deadline is calculated.

At each exclusion opportunity, Participants may exclude patent claims with respect to a body of text. The Exclusion Draft is the reference body of text for the current exclusion opportunity.

Note: At each new exclusion opportunity (e.g., in the case of a second Candidate Recommendation Snapshot), exclusions are only with respect to differences since the previous reference body of text. These differences may be less than an entire document, and the summary below does not address that granularity. Also, in some edge cases (discussed in the FAQ), Participants, depending on when they joined the Working Group, will have different Exclusion Drafts; the summary below does not reflect this case.

Exclusion Opportunities

CSS Viewport Module Level 1
Call for exclusion started on 2024-01-25, opportunity until 2024-06-23

View previous exclusion opportunities

CSS Transitions Level 2
Call for exclusion started on 2023-09-05, opportunity until 2024-02-02
CSS Anchor Positioning
Call for exclusion started on 2023-06-29, opportunity until 2023-11-26
CSS View Transitions Module Level 1
Call for exclusion started on 2023-09-05, opportunity until 2023-11-04
CSS Animations Level 2
Call for exclusion started on 2023-03-02, opportunity until 2023-07-30
Web Animations Level 2
Call for exclusion started on 2023-02-21, opportunity until 2023-07-21
CSS Display Module Level 3
Call for exclusion started on 2023-03-30, opportunity until 2023-05-29
CSS View Transitions Module Level 1
Call for exclusion started on 2022-10-25, opportunity until 2023-03-24
Scroll-linked Animations
Call for exclusion started on 2022-10-25, opportunity until 2023-03-24
CSS Values and Units Module Level 3
Call for exclusion started on 2022-12-01, opportunity until 2023-01-30
CSS Containment Module Level 1
Call for exclusion started on 2022-10-26, opportunity until 2022-12-25
CSS Color Module Level 4
Call for exclusion started on 2022-07-05, opportunity until 2022-09-03
CSS Custom Properties for Cascading Variables Module Level 1
Call for exclusion started on 2022-06-16, opportunity until 2022-08-15
Media Queries Level 3
Call for exclusion started on 2022-04-05, opportunity until 2022-06-04
CSS Cascading and Inheritance Level 6
Call for exclusion started on 2021-12-21, opportunity until 2022-05-20
CSS Conditional Rules Module Level 5
Call for exclusion started on 2021-12-21, opportunity until 2022-05-20
CSS Containment Module Level 3
Call for exclusion started on 2021-12-21, opportunity until 2022-05-20
CSS Conditional Rules Module Level 4
Call for exclusion started on 2022-02-17, opportunity until 2022-04-18
CSS Color Adjustment Module Level 1
Call for exclusion started on 2022-02-10, opportunity until 2022-04-11
CSS Cascading and Inheritance Level 4
Call for exclusion started on 2022-01-13, opportunity until 2022-03-14
CSS Cascading and Inheritance Level 5
Call for exclusion started on 2022-01-13, opportunity until 2022-03-14
CSS Conditional Rules Module Level 3
Call for exclusion started on 2022-01-13, opportunity until 2022-03-14
CSS Scrollbars Styling Module Level 1
Call for exclusion started on 2021-12-09, opportunity until 2022-02-07
CSS Nesting Module
Call for exclusion started on 2021-08-31, opportunity until 2022-01-28
CSS Multi-column Layout Module Level 1
Call for exclusion started on 2021-10-12, opportunity until 2021-12-11
CSS Fonts Module Level 5
Call for exclusion started on 2021-06-29, opportunity until 2021-11-26
CSS Counter Styles Level 3
Call for exclusion started on 2021-07-27, opportunity until 2021-09-25
CSS Cascading and Inheritance Level 5
Call for exclusion started on 2021-01-19, opportunity until 2021-06-18
CSS Scroll Snap Module Level 1
Call for exclusion started on 2021-03-11, opportunity until 2021-05-10
CSS Custom Highlight API Module Level 1
Call for exclusion started on 2020-10-22, opportunity until 2021-03-21
CSS Text Module Level 3
Call for exclusion started on 2020-12-22, opportunity until 2021-02-20
CSS Box Model Module Level 3
Call for exclusion started on 2020-12-22, opportunity until 2021-02-20
CSS Backgrounds and Borders Module Level 3
Call for exclusion started on 2020-12-22, opportunity until 2021-02-20
CSS Conditional Rules Module Level 3
Call for exclusion started on 2020-12-08, opportunity until 2021-02-06
CSS Box Sizing Module Level 4
Call for exclusion started on 2020-05-26, opportunity until 2020-10-23
CSS Grid Layout Module Level 1
Call for exclusion started on 2020-08-18, opportunity until 2020-10-17
CSS Grid Layout Module Level 2
Call for exclusion started on 2020-08-18, opportunity until 2020-10-17
Media Queries Level 4
Call for exclusion started on 2020-07-21, opportunity until 2020-09-19
CSS Box Model Module Level 4
Call for exclusion started on 2020-04-21, opportunity until 2020-09-18
Media Queries Level 5
Call for exclusion started on 2020-03-03, opportunity until 2020-07-31
CSS Transforms Module Level 2
Call for exclusion started on 2020-03-03, opportunity until 2020-07-31
CSS Conditional Rules Module Level 4
Call for exclusion started on 2020-03-03, opportunity until 2020-07-31
CSS Color Module Level 5
Call for exclusion started on 2020-03-03, opportunity until 2020-07-31
CSS Scroll Anchoring Module Level 1
Call for exclusion started on 2020-02-11, opportunity until 2020-07-10
Resize Observer
Call for exclusion started on 2020-02-11, opportunity until 2020-07-10
CSS Speech Module
Call for exclusion started on 2020-03-10, opportunity until 2020-05-09
CSS Containment Module Level 2
Call for exclusion started on 2019-10-15, opportunity until 2020-03-13
CSS Images Module Level 3
Call for exclusion started on 2019-10-10, opportunity until 2019-12-09
CSS Animation Worklet API
Call for exclusion started on 2019-06-25, opportunity until 2019-11-22
CSS Overscroll Behavior Module Level 1
Call for exclusion started on 2019-06-06, opportunity until 2019-11-03
CSS Writing Modes Level 3
Call for exclusion started on 2019-09-03, opportunity until 2019-11-02
CSS Color Adjust Module Level 1
Call for exclusion started on 2019-05-21, opportunity until 2019-10-18
CSS Text Decoration Module Level 3
Call for exclusion started on 2019-08-13, opportunity until 2019-10-12
CSS Writing Modes Level 4
Call for exclusion started on 2019-07-30, opportunity until 2019-09-28
CSS Writing Modes Level 3
Call for exclusion started on 2019-07-30, opportunity until 2019-09-28
CSS Spatial Navigation Level 1
Call for exclusion started on 2019-04-23, opportunity until 2019-09-20
CSS Syntax Module Level 3
Call for exclusion started on 2019-07-16, opportunity until 2019-09-14
CSS Display Module Level 3
Call for exclusion started on 2019-07-11, opportunity until 2019-09-09
CSS Values and Units Module Level 3
Call for exclusion started on 2019-06-06, opportunity until 2019-08-05
CSS Containment Module Level 1
Call for exclusion started on 2019-04-30, opportunity until 2019-06-29
CSS Easing Functions Level 1
Call for exclusion started on 2019-04-30, opportunity until 2019-06-29
CSS Fragmentation Module Level 4
Call for exclusion started on 2018-12-18, opportunity until 2019-05-17
CSS Transforms Module Level 1
Call for exclusion started on 2019-02-14, opportunity until 2019-04-15
CSS Shadow Parts
Call for exclusion started on 2018-11-15, opportunity until 2019-04-14
CSS Scroll Snap Module Level 1
Call for exclusion started on 2019-01-31, opportunity until 2019-04-01
CSS Values and Units Module Level 3
Call for exclusion started on 2019-01-31, opportunity until 2019-04-01
CSS Scrollbars Module Level 1
Call for exclusion started on 2018-09-25, opportunity until 2019-02-22
CSS Fragmentation Module Level 3
Call for exclusion started on 2018-12-04, opportunity until 2019-02-02
Geometry Interfaces Module Level 1
Call for exclusion started on 2018-12-04, opportunity until 2019-02-02
CSS Values and Units Module Level 4
Call for exclusion started on 2018-08-14, opportunity until 2019-01-11
CSS Flexible Box Layout Module Level 1
Call for exclusion started on 2018-11-08, opportunity until 2019-01-07
CSS Containment Module Level 1
Call for exclusion started on 2018-11-08, opportunity until 2019-01-07
CSS Cascading and Inheritance Level 4
Call for exclusion started on 2018-08-28, opportunity until 2018-10-27
CSS Display Module Level 3
Call for exclusion started on 2018-08-28, opportunity until 2018-10-27
CSS Cascading and Inheritance Level 3
Call for exclusion started on 2018-08-28, opportunity until 2018-10-27
CSS Values and Units Module Level 3
Call for exclusion started on 2018-08-14, opportunity until 2018-10-13
CSS Scroll Snap Module Level 1
Call for exclusion started on 2018-08-14, opportunity until 2018-10-13
CSS Painting API Level 1
Call for exclusion started on 2018-08-09, opportunity until 2018-10-08
CSS Layout API Level 1
Call for exclusion started on 2018-04-12, opportunity until 2018-09-09
CSS Text Decoration Module Level 3
Call for exclusion started on 2018-07-03, opportunity until 2018-09-01
CSS Fonts Module Level 3
Call for exclusion started on 2018-06-26, opportunity until 2018-08-25
CSS Text Decoration Module Level 4
Call for exclusion started on 2018-03-13, opportunity until 2018-08-10
CSS Containment Module Level 1
Call for exclusion started on 2018-05-24, opportunity until 2018-07-23
CSS Writing Modes Level 4
Call for exclusion started on 2018-05-24, opportunity until 2018-07-23
CSS Writing Modes Level 3
Call for exclusion started on 2018-05-24, opportunity until 2018-07-23
CSS Grid Layout Module Level 2
Call for exclusion started on 2018-02-06, opportunity until 2018-07-06
CSS Fonts Module Level 3
Call for exclusion started on 2018-03-15, opportunity until 2018-05-14
CSS Writing Modes Level 4
Call for exclusion started on 2017-12-07, opportunity until 2018-05-06
Selectors Level 3
Call for exclusion started on 2018-01-30, opportunity until 2018-03-31
CSS Grid Layout Module Level 1
Call for exclusion started on 2017-12-14, opportunity until 2018-02-12
CSS Counter Styles Level 3
Call for exclusion started on 2017-12-14, opportunity until 2018-02-12
CSS Scroll Snap Module Level 1
Call for exclusion started on 2017-12-14, opportunity until 2018-02-12
CSS Writing Modes Level 3
Call for exclusion started on 2017-12-07, opportunity until 2018-02-05
CSS Color Module Level 3
Call for exclusion started on 2017-12-05, opportunity until 2018-02-03
CSS Flexible Box Layout Module Level 1
Call for exclusion started on 2017-10-19, opportunity until 2017-12-18
CSS Backgrounds and Borders Module Level 3
Call for exclusion started on 2017-10-17, opportunity until 2017-12-16
CSS Fonts Module Level 4
Call for exclusion started on 2017-07-11, opportunity until 2017-12-08
CSS Overflow Module Level 4
Call for exclusion started on 2017-06-13, opportunity until 2017-11-10
Media Queries Level 4
Call for exclusion started on 2017-09-05, opportunity until 2017-11-04
CSS Scroll Snap Module Level 1
Call for exclusion started on 2017-08-24, opportunity until 2017-10-23
CSS Logical Properties and Values Level 1
Call for exclusion started on 2017-05-18, opportunity until 2017-10-15
CSS Containment Module Level 1
Call for exclusion started on 2017-08-08, opportunity until 2017-10-07
CSS Fill and Stroke Module Level 3
Call for exclusion started on 2017-04-13, opportunity until 2017-09-10
CSS Rhythmic Sizing
Call for exclusion started on 2017-03-02, opportunity until 2017-07-30
CSS Timing Functions Level 1
Call for exclusion started on 2017-02-21, opportunity until 2017-07-21
CSS Containment Module Level 1
Call for exclusion started on 2017-02-21, opportunity until 2017-07-21
CSS Grid Layout Module Level 1
Call for exclusion started on 2017-05-09, opportunity until 2017-07-08
CSS Basic User Interface Module Level 3 (CSS3 UI)
Call for exclusion started on 2017-03-02, opportunity until 2017-05-01
CSS Table Module Level 3
Call for exclusion started on 2016-10-25, opportunity until 2017-03-24
CSS Scroll Snap Module Level 1
Call for exclusion started on 2016-10-24, opportunity until 2016-12-23
CSS Color Module Level 4
Call for exclusion started on 2016-07-05, opportunity until 2016-12-02
CSS Grid Layout Module Level 1
Call for exclusion started on 2016-09-29, opportunity until 2016-11-28
Worklets Level 1
Call for exclusion started on 2016-06-07, opportunity until 2016-11-04
CSS Painting API Level 1
Call for exclusion started on 2016-06-07, opportunity until 2016-11-04
CSS Properties and Values API Level 1
Call for exclusion started on 2016-06-07, opportunity until 2016-11-04
CSS Typed OM Level 1
Call for exclusion started on 2016-06-07, opportunity until 2016-11-04
Cascading Style Sheets Level 2 Revision 2 (CSS 2.2) Specification
Call for exclusion started on 2016-04-12, opportunity until 2016-09-09
CSS Flexible Box Layout Module Level 1
Call for exclusion started on 2016-05-26, opportunity until 2016-07-25
CSS Flexible Box Layout Module Level 1
Call for exclusion started on 2016-03-02, opportunity until 2016-05-01
CSS Fragmentation Module Level 3
Call for exclusion started on 2016-01-14, opportunity until 2016-03-14
CSS Cascading and Inheritance Level 4
Call for exclusion started on 2016-01-14, opportunity until 2016-03-14
CSS Round Display Level 1
Call for exclusion started on 2015-09-23, opportunity until 2016-02-20
CSS Text Module Level 4
Call for exclusion started on 2015-09-23, opportunity until 2016-02-20
CSS Basic User Interface Module Level 4
Call for exclusion started on 2015-09-23, opportunity until 2016-02-20
CSS Namespaces Module
Call for exclusion started on 2015-12-17, opportunity until 2016-02-15
CSS Page Floats
Call for exclusion started on 2015-09-16, opportunity until 2016-02-13
CSS Writing Modes Level 3
Call for exclusion started on 2015-12-15, opportunity until 2016-02-13
CSS Will Change Module Level 1
Call for exclusion started on 2015-12-04, opportunity until 2016-02-02
CSS Custom Properties for Cascading Variables Module Level 1
Call for exclusion started on 2015-12-04, opportunity until 2016-02-02
CSS Cascading and Inheritance Level 4
Call for exclusion started on 2015-04-21, opportunity until 2015-09-18
CSS Flexible Box Layout Module Level 1
Call for exclusion started on 2015-07-15, opportunity until 2015-09-13
Motion Path Module Level 1
Call for exclusion started on 2015-04-09, opportunity until 2015-09-06
CSS Basic User Interface Module Level 3 (CSS3 UI)
Call for exclusion started on 2015-07-07, opportunity until 2015-09-05
CSS Scroll Snap Points Module Level 1
Call for exclusion started on 2015-03-26, opportunity until 2015-08-23
CSS Values and Units Module Level 3
Call for exclusion started on 2015-06-11, opportunity until 2015-08-10
CSS Counter Styles Level 3
Call for exclusion started on 2015-06-11, opportunity until 2015-08-10
CSS Cascading and Inheritance Level 3
Call for exclusion started on 2015-04-20, opportunity until 2015-06-19
CSS Pseudo-Elements Module Level 4
Call for exclusion started on 2015-01-16, opportunity until 2015-06-15
CSS Inline Layout Module Level 3
Call for exclusion started on 2014-12-19, opportunity until 2015-05-18
CSS Counter Styles Level 3
Call for exclusion started on 2015-02-03, opportunity until 2015-04-04
Compositing and Blending Level 1
Call for exclusion started on 2015-01-14, opportunity until 2015-03-15
CSS Flexible Box Layout Module Level 1
Call for exclusion started on 2014-09-25, opportunity until 2014-11-24
Media Queries Level 4
Call for exclusion started on 2014-06-05, opportunity until 2014-11-02
Non-element Selectors Module Level 1
Call for exclusion started on 2014-06-03, opportunity until 2014-10-31
CSS Counter Styles Level 3
Call for exclusion started on 2014-08-28, opportunity until 2014-10-27
Geometry Interfaces Module Level 1
Call for exclusion started on 2014-05-22, opportunity until 2014-10-19
CSS Will Change Module Level 1
Call for exclusion started on 2014-05-01, opportunity until 2014-09-28
CSS Line Grid Module Level 1
Call for exclusion started on 2014-04-03, opportunity until 2014-08-31
CSS Scoping Module Level 1
Call for exclusion started on 2014-04-03, opportunity until 2014-08-31
Geometry Interfaces Module Level 1
Call for exclusion started on 2014-06-26, opportunity until 2014-08-25
CSS Font Loading Module Level 3
Call for exclusion started on 2014-05-22, opportunity until 2014-07-21
CSS Masking Module Level 1
Call for exclusion started on 2014-05-22, opportunity until 2014-07-21
CSS Display Module Level 3
Call for exclusion started on 2014-02-20, opportunity until 2014-07-20
CSS Font Loading Module Level 3
Call for exclusion started on 2014-02-20, opportunity until 2014-07-20
CSS Font Loading Module Level 3
Call for exclusion started on 2014-02-20, opportunity until 2014-07-20
CSS Custom Properties for Cascading Variables Module Level 1
Call for exclusion started on 2014-05-06, opportunity until 2014-07-05
CSS Flexible Box Layout Module Level 1
Call for exclusion started on 2014-03-26, opportunity until 2014-05-25
CSS Shapes Module Level 1
Call for exclusion started on 2014-02-12, opportunity until 2014-04-13
CSS Backgrounds and Borders Module Level 3
Call for exclusion started on 2014-02-04, opportunity until 2014-04-05
Compositing and Blending Level 1
Call for exclusion started on 2014-01-07, opportunity until 2014-03-08
DOMMatrix interface
Call for exclusion started on 2013-09-21, opportunity until 2014-02-18
CSS Shapes Module Level 1
Call for exclusion started on 2013-12-03, opportunity until 2014-02-01
CSS Writing Modes Level 3
Call for exclusion started on 2013-11-26, opportunity until 2014-01-25
CSS Syntax Module Level 3
Call for exclusion started on 2013-11-06, opportunity until 2014-01-05
CSS Masking Module Level 1
Call for exclusion started on 2013-10-30, opportunity until 2013-12-29
CSS Masking Module Level 1
Call for exclusion started on 2013-10-29, opportunity until 2013-12-28
Compositing and Blending Level 1
Call for exclusion started on 2013-10-11, opportunity until 2013-12-10
CSS Text Module Level 3
Call for exclusion started on 2013-10-10, opportunity until 2013-12-09
Web Animations 1.0
Call for exclusion started on 2013-06-25, opportunity until 2013-11-22
CSS Shapes Module Level 1
Call for exclusion started on 2013-06-21, opportunity until 2013-11-18
CSS Cascading and Inheritance Level 3
Call for exclusion started on 2013-07-30, opportunity until 2013-09-28
CSS Counter Styles Level 3
Call for exclusion started on 2013-07-18, opportunity until 2013-09-16
CSS Overflow Module Level 3
Call for exclusion started on 2013-04-18, opportunity until 2013-09-15
CSS Fonts Module Level 3
Call for exclusion started on 2013-07-12, opportunity until 2013-09-10
CSS Custom Properties for Cascading Variables Module Level 1
Call for exclusion started on 2013-06-21, opportunity until 2013-08-20
CSS Masking
Call for exclusion started on 2012-11-15, opportunity until 2013-04-14
Filter Effects 1.0
Call for exclusion started on 2012-10-25, opportunity until 2013-03-24
CSS Counter Styles Level 3
Call for exclusion started on 2012-10-09, opportunity until 2013-03-08
CSS Text Decoration Module Level 3
Call for exclusion started on 2013-01-03, opportunity until 2013-03-04
CSS Intrinsic & Extrinsic Sizing Module Level 3
Call for exclusion started on 2012-09-27, opportunity until 2013-02-24
CSS Conditional Rules Module Level 3
Call for exclusion started on 2012-12-13, opportunity until 2013-02-11
CSS Image Values and Replaced Content Module Level 4
Call for exclusion started on 2012-09-11, opportunity until 2013-02-08
Compositing and Blending 1.0
Call for exclusion started on 2012-08-21, opportunity until 2013-01-18
Compositing and Blending 1.0
Call for exclusion started on 2012-08-16, opportunity until 2013-01-13
Fullscreen
Call for exclusion started on 2012-07-03, opportunity until 2012-11-30
CSS Box Alignment Module Level 3
Call for exclusion started on 2012-06-13, opportunity until 2012-11-10
CSS Variables Module Level 1
Call for exclusion started on 2012-04-10, opportunity until 2012-09-07
CSS Flexible Box Layout Module
Call for exclusion started on 2012-06-13, opportunity until 2012-08-12
CSS Fragmentation Module Level 3
Call for exclusion started on 2012-03-13, opportunity until 2012-08-10
CSS Fragmentation Module Level 3
Call for exclusion started on 2012-03-12, opportunity until 2012-08-09
CSS Positioned Layout Module Level 3
Call for exclusion started on 2012-02-08, opportunity until 2012-07-07
CSS Backgrounds and Borders Module Level 3
Call for exclusion started on 2012-03-12, opportunity until 2012-05-11
CSS Values and Units Module Level 3
Call for exclusion started on 2012-03-12, opportunity until 2012-05-11
CSS Exclusions and Shapes Module Level 3
Call for exclusion started on 2011-12-13, opportunity until 2012-05-11
CSS Image Values and Replaced Content Module Level 3
Call for exclusion started on 2012-01-12, opportunity until 2012-03-12
Selectors Level 4
Call for exclusion started on 2011-09-29, opportunity until 2012-02-26
CSS3 Ruby Module
Call for exclusion started on 2011-09-19, opportunity until 2012-02-16
CSS Device Adaptation
Call for exclusion started on 2011-09-15, opportunity until 2012-02-12
CSS Conditional Rules Module Level 3
Call for exclusion started on 2011-09-12, opportunity until 2012-02-09
CSSOM
Call for exclusion started on 2011-09-12, opportunity until 2012-02-09
CSS Speech Module
Call for exclusion started on 2011-09-12, opportunity until 2011-11-11
CSS Regions Module
Call for exclusion started on 2011-06-09, opportunity until 2011-11-06
Grid Layout
Call for exclusion started on 2011-04-07, opportunity until 2011-09-04
Cascading Style Sheets (CSS) Snapshot 2010
Call for exclusion started on 2010-12-07, opportunity until 2011-05-06
Cascading Style Sheets (CSS) Snapshot 2007
Call for exclusion started on 2010-07-27, opportunity until 2010-09-25
CSS Backgrounds and Borders Module Level 3
Call for exclusion started on 2010-06-15, opportunity until 2010-08-14
Flexible Box Layout Module
Call for exclusion started on 2009-07-23, opportunity until 2009-12-20
CSS Image Values Module Level 3
Call for exclusion started on 2009-07-23, opportunity until 2009-12-20
CSS Backgrounds and Borders Module Level 3
Call for exclusion started on 2009-10-15, opportunity until 2009-12-14
Media Queries
Call for exclusion started on 2009-04-23, opportunity until 2009-09-20
CSS3 module: Multi-column layout
Call for exclusion started on 2009-06-30, opportunity until 2009-08-29
CSS 2D Transforms Module Level 3
Call for exclusion started on 2009-03-23, opportunity until 2009-08-20
CSS 3D Transforms Module Level 3
Call for exclusion started on 2009-03-23, opportunity until 2009-08-20
CSS Animations Module Level 3
Call for exclusion started on 2009-03-23, opportunity until 2009-08-20
CSS Transitions Module Level 3
Call for exclusion started on 2009-03-23, opportunity until 2009-08-20
Selectors Level 3
Call for exclusion started on 2009-03-10, opportunity until 2009-05-09
CSS Marquee Module Level 3
Call for exclusion started on 2008-08-01, opportunity until 2008-09-30
CSS Color Module Level 3
Call for exclusion started on 2008-07-22, opportunity until 2008-09-20
CSSOM View Module
Call for exclusion started on 2008-02-28, opportunity until 2008-07-27
CSS Namespaces Module
Call for exclusion started on 2008-02-15, opportunity until 2008-04-15
Cascading Style Sheets (CSS) Snapshot 2007
Call for exclusion started on 2007-10-19, opportunity until 2008-03-17
CSS Grid Positioning Module Level 3
Call for exclusion started on 2007-09-11, opportunity until 2008-02-08
CSS Mobile Profile 2.0
Call for exclusion started on 2007-10-19, opportunity until 2007-12-18
Cascading Style Sheets, level 2 revision 1
Call for exclusion started on 2006-11-06, opportunity until 2007-01-05

Additional Licensing Information

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All Working Group participants are encouraged to provide a contact from which licensing information can be obtained and other relevant licensing information. Any such information will be made publicly available along with the patent disclosures for the Working Group in question.

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