Copyright rules

I have downloaded works from the Internet which are in the public domain in the U.S.A and other countries.  This is my question: am I perhaps infringing anyone's copyright by keeping these files for personal use? Is it okay to keep them just for personal use?

I am awfully confused with regards to the law on copyright and other connected terms. Thank you very much in advance.  

Yours sincerely,
anonymous

As long as they have been made available for the general consumption of the public and was not pirated illegally, I don't see why not.

Just remember that it is for your own personal use. It should not go beyond that, nor should you make any money off of those files.

So would this also mean that I am not allowed to share these files to others if for instance someone would want a copy?

You have to make sure first that the file you wish to share is already intended to be PART OF THE PUBLIC DOMAIN. For all we know, what you have might be a floating pirated copy of the book that the author did not consent to be shared to the world for free.

To be sure, you should contact the author (or the US agency related to public domain matters) to verify if the file you wish to share is really part of the public domain. If not, you should formally ask for his permission if you could share his work with others.

I think they are since the authors of these books are already dead and the people who are responsible for sharing these files checked if the books are copyrighted.  

And because these are Catholic books, large and small organizations are doing their best to share these files to the world for free, I am concerned however of possible conflicts between the laws in the US and the Philippines.

That is, a book might be in the public domain in the USA while still under copyright here in the Philippines.  

(1) If I have downloaded a book that is in the public domain in the US, but might not be here in the Philippines, am I still able to legitimately use these files for personal use?

(2) If I am able to legitimately use these files, can I share them for free, within my own physical range that is without the use of the internet?

Thank you very much in advance.

I don't think there will be a conflict in the PH, unless those authors have a standing contract with a publisher here locally that establishes their right to distribute the books here in our locality.

To be totally sure, you should contact the Intellectual Property Office and ask your queries there, since they have the repository of copyrighted materials that are registered in the PH.

Good luck.