It is proper Netiquette to protect your content by crediting the source. Don't use others work without attribution.
Ownership of intellectual property is determined by the creator. We own the information we create. Digital Rights Management allows us to purchase viewership of videos and access. Crediting sources informs others of ownership.
Always claim a copyright for material that you upload. It is yours if you upload it or it should not be on your computer. Provide your name and address with video uploads.
Credit sources because content without attribution or right may be infringement.