Update CONTRIBUTING.md (#4585)

- per centralized updates

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CONTRIBUTING.md

@@ -244,13 +244,15 @@ The following PR has one non-blocking review, one blocking review, one approval,
 
 ### Contributor License Agreement
 
-In order to contribute to this project, the Unicode Consortium must have on file a Contributor License Agreement (CLA) covering your contributions, either an individual or a corporate CLA. Pull Requests will not be merged until the correct CLA is signed. Which version needs to be signed depends on who owns the contribution being made: you as the individual making the contribution or your employer. _It is your responsibility to determine whether your contribution is owned by your employer._ Please review [The Unicode Consortium Intellectual Property, Licensing, and Technical Contribution Policies][policies] for further guidance on which CLA to sign, as well as other information and guidelines regarding the Consortium’s licensing and technical contribution policies and procedures.
+In order to contribute to this project, the Unicode Consortium must have on file a Contributor License Agreement (CLA) covering your contributions, either an individual or a corporate CLA. Pull Requests, issues, and other contributions will not be merged/accepted until the correct CLA is signed. Which version needs to be signed depends on who owns the contribution being made: you as the individual making the contribution or your employer. **It is your responsibility to determine whether your contribution is owned by your employer.** Please review the [Unicode Intellectual Property, Licensing, & Technical Contribution Policy][policies] for further guidance on which CLA to sign, as well as other information and guidelines regarding the Consortium’s licensing and technical contribution policies and procedures.
 
-- **Individual CLA**: If you have determined that the Individual CLA is appropriate, just open a Pull Request and you will have the opportunity to click to accept the Individual CLA.
+To sign the CLA in Github, open a Pull Request (a comment will be automatically added with a link to the CLA Form), or go directly to [the CLA Form][sign-cla]. You may need to sign in to Github to see the entire CLA Form.
 
-- **Corporate CLA**: If you have determined that a Corporate CLA is appropriate, please check the [public list of Corporate CLAs][unicode-corporate-clas] that the Consortium has on file. If your employer has already signed a CLA, then just open a Pull Request and you will have the opportunity to click that your employer has already signed a CLA. If your employer has not already signed a CLA, you will need to arrange for your employer to sign the Corporate CLA, as described in [How to Sign a Unicode CLA][signing].
+- **Individual CLA**: If you have determined that the Individual CLA is appropriate, then when you access the CLA Form, click the Individual CLA and complete the Form.
 
-Unless otherwise noted in the [LICENSE](./LICENSE) file, this project is released under the free and open-source [Unicode License][unicode-license], also known as Unicode, Inc. License Agreement - Data Files and Software.
+- **Corporate CLA**: If you have determined that a Corporate CLA is appropriate, please first check the [public list of Corporate CLAs][unicode-corporate-clas] that the Consortium has on file. If your employer is listed, then when you access the CLA Form, you can click the box indicating that you are covered by your employer’s corporate CLA. If your employer is not on the list, then it has not already signed a CLA and you will need to arrange for your employer to do so before you contribute, as described in [How to Sign a Unicode CLA][signing].
+
+Unless otherwise noted in the [LICENSE](./LICENSE) file, this project is released under the [OSI-approved][osi-Unicode-License-3.0] free and open-source [Unicode License v3][unicode-license].
 
 ### New files
 
@@ -326,3 +328,5 @@ Please discuss first.
 [unicode-corporate-clas]: https://www.unicode.org/policies/corporate-cla-list/
 [signing]: https://www.unicode.org/policies/licensing_policy.html#signing
 [unicode-license]: https://www.unicode.org/license.txt
+[sign-cla]: https://cla-assistant.io/unicode-org/.github
+[osi-Unicode-License-3.0]: https://opensource.org/license/unicode-license-v3/