Yahoo claims ownership?

how is it legally possible that yahoo can claim ownership and/or copyright of my literary works that I choose to post?

By submission am I transferring my rights?

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Yes, you are giving up the rights to what you write upon posting them. It's like that at a great many public forums and boards, IMDb among them.

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Yes it be part of the T&Cs Read the agreement you agreed to when you signed on. It will tell you everything.

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