You can limit YouTube search results to Creative Commons content as well.
Once you have submitted a search request, click the "Filter" icon. Under the "Features" column, click on "Creative Commons"

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YouTube videos are considered OER when a Creative Commons license is listed in the video's description.
Note: you may have to click on "show more" in order to see the video's license.

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Disclaimer: YouTube videos with Creative Commons licensing have the potential to be incorrectly licensed. For example, a user may upload a video containing copyrighted material, such as a lecture or performance recording, but choose to license their video under Creative Commons. If the user did not obtain permission to use this material, their video cannot be considered open. Be sure to evaluate these videos as you would any other online material. If you have any questions or concerns about using YouTube videos in your instruction, contact Open Fredonia for more information.