I am assuming you are in the US? I'll assume you are.

The fact that the patent has been approved proves that in the it can be, its a precedent and US law is precedent bound.

As for lawyers, no you'll have to pay for your own lawyers.

I will try to answer the question clearly.

1) A patent once issued is a legal instrument granting a monopoly. The fact that it issued means that the examiner either did not know the prior art or knew it and thought the claims differed. This is a very important distinction as it means the difference between winning and losing in litigation. Many clients come in convinced that something was known beforehand whereas the claim is specific about something new and inventive.

2) The reference must have been published over a year before filing to be certainly citable.

3) If you are sued, you will need to cover your own costs at least through the trial phase.

4) The courts can award costs in patent cases but the criteria is strict, ambiguously applied, and rarely returns all costs, so I would be careful.

What I most often recommend is that you put the prior art together for your files (sometimes things get forgotten and the lack of filing is problematic, so build the file). Make sure you cover off everything in each and every claim. Then get someone to look at it and at least give you a verbal, "you got it right" (this will be somewhat expensive)). After that, you have some defense in relation to litigation.

You can also file for a re-examination if you really believe that all the subject matter is invalid. That said, it may just lead to them focusing their claims more narrowly and therefore cause more problems than it solves.

I have handled a lot of issues like these over the course of my career and each one requires a slightly varied solution, so a simple solution statement is not possible without the facts.

Sorry that I cannot be more helpful.

This question is written "yes" or "no." While I can't say it that succinctly, let me take a shot at this. To be patentable, an idea must have 1. utility, 2. novelty, and 3. be non-obvious. If you assume that the idea has utility, then we address novelty. Novelty asks if this particular thing has ever been done before. There are new ideas every day. So, many ideas pass this bar easily. Next is non-obviousness. This is where a lot of things get hung up. You can't patent something that would be "obvious" to try or do by someone skilled in the art of the particular field.

Now, lets get to what seems to be a question dealing with public domain and the 1 year filing thing. If you have a patentable idea, you have 1 year to file from the date that you disclose the idea. Thus, if you don't file within a year of disclosure, then you are barred from filing. Why? Well, remember the idea has to be novel! If its been out there in the public for a year, then when you go to file, that idea isn't novel any longer. Your own conduct of disclosing your idea becomes a bar to your own patentability. We call that 1 year the "safe harbor" to give you a little time to get your "stuff" together.

Now, lets say you want to practice something and are afraid a third-party will claim patent rights. If its been disclosed more than a year and the inventor has not filed a patent, then the inventor will not be able to get a patent...and thus won't have anything to sue you for.

Hope that helps.