Just curious if well recognized literary agents or publishers would ever consider stealing your work? Say, if they sent back your manuscript with a reject slip...would you think that there would be any way that they would go behind your back and try to publish your work anyways?

All Answers To Questions

No. They would very soon put themselves out of business if they did things like that.

No. They could try and any ensuing lawsuit would put them out of business because even if you didn't register the work for an official copyright(and any novel or piece of writing that is being sent to publishers or agents should be registered with the copyright office) the work is still unofficially copyrighted under the intellectual copyright idea that as soon as you write the piece it is copyrighted. It's harder to prove but possible.

That is why it is always wise to send in only a copy and not the original format of one's manuscript. Literary agents or publishers could be SUED if they steal anyone's work. That is one consolation for you. It is very wise, too, to get a copyright just in case that happens. Publishing is synonymous to getting that copyright for protecting your book which is why it is highly important to publish it. You may probably decide which way you want to go if you have exhausted all options. perhaps its best still if you happen to have a publishing plan mapped out and then go from there. In the meantime, I'll give you something to peruse while you are at it. Let me know if you have questions. :)