(Once more: I am not a lawyer, but my lawyer friends can answer questions if medyo di ko na kaya.)
You already have copyright over your work, published or unpublished, as soon as you create it. As in pagkasulat mo (kung story sya), may copyright na yan, at iyo na. Kahit wala pang nakakakita. Kahit hindi pa online. Basta nasulat mo na.
Ang pag-register ng copyright ay para sa additional protection ng work mo. Hindi ibig sabihin na walang copyright, if hindi registered. Please see previous paragraph. :)
Kung concerned ka na baka ma-plagiarize o ma-pirate ang kwento mo, copyright registration will not prevent that from happening. As long as you can prove na ikaw ang unang nagsulat ng kwento, ikaw pa rin ang orig.
Ang pag-post sa Wattpad actually helps build your case for ownership of your story, if may instance na may manggaya sa work mo. Kasi based sa published date, ikaw ang una.
Sa piracy naman... isipin na lang lahat ng bagay a napa-pirate at protected naman ng copyright at kung ano pang laws. Obviously hindi niya napre-prevent ito.
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If you signed over copyright to a company, then THEY own the story. They decide what happens to it. They can decide na hindi na ikaw ang magsusulat ng mga karagdagang kwento. O pwede namang ikaw pa rin, pero sa halagang gusto nila. Hindi ikaw ang makakapagsabi nito.
Yes, ikaw pa rin ang author, pero wala ka nang karapatang magdesisyon about the future of the story or anything else related to it. Ang publisher na ang may copyright eh.
BINABASA MO ANG
Publishing and Self-publishing: Advice for Writers
Non-Fiction[FILIPINO/ENGLISH] Advice for writers based on my experience self-publishing (more than 20 novels as of now) and traditional publishing (more than 10 novels with a traditional publisher, and consulting for other fellow authors). Read and learn, but...