First, to be clear, the USPTO deals only with patent and trademark protections. If you want to copyright something in the US, you need to correspond with the US Copyright Office. You can find information on the Copyright Office here: http://www.copyright.gov/
You cannot copyright protect an idea--under intellectual property law, in order to secure protection, whether it be patent, trademark, or copyright, an "idea" generally must be committed to some kind of tangible medium where the idea is embodied in some actual form (e.g., a drawing, a physical object of some sort, written words, etc.).
That said, you can copyright your business plan--in fact, by writing the business plan down you already have common law copyright rights in that writing. But, you should note that the copyright protects the writing itself from others making unauthorized copies, but NOT the idea underlying the business/writing.
The best bet for protecting the new business idea, I would think, is to keep it as a trade secret (for now, at least):
A trade secret is a formula, practice, process, design, instrument, pattern, or compilation of information which is not generally known or reasonably ascertainable, by which a business can obtain an economic advantage over competitors or customers. In some jurisdictions, such secrets are referred to as "confidential information" or "classified information". See http://en.wikipedia.org/wiki/Trade_secret
You likely would want to use Confidentiality Agreements to keep the fundamentals of the new business secure. Otherwise, depending on the business type and other issues, you may be able to seek a patent on the business method--however, that is a complicated issue and without knowing more I cannot comment further other than saying discussing your idea with an attorney and getting such protection would be confidential and you would want to discuss it with an expert in the area.
You can copyright a written business plan by filing a simple document with the Copyright Office. However, merely registering your copyright in the business plan document will probably not provide your new business with much meaningful protection.
If you wish to prevent competitors from starting businesses with similar business plans, then you should be thinking about whether there are new, useful, and non-obvious aspects of your business plan that you can patent. That said, at the present time, so-called "business method" patents are somewhat out of favor with the USPTO. For example, it would be challenging to get patent protection on the mere idea of "selling ice cream bars for home delivery via a web interface," assuming that were your business plan. However, it would be a different story if you came up with novel and non-obvious ways to keep ice cream frozen while it is being delivered after having been ordered via a web interface. A patent attorney should be able to help you sort out whether your business plan includes any features that are likely to be patentable.
Additionally, once you have settled on a brand or name for the business, you should consider filing a trademark application to prevent others from using a similar name in association with similar services.
You cannot protect an idea for a business. However, I would advise you to get in touch with a patent attorney who can help you obtain a PATENT on the technology behind your business idea. Also keep in mind that you can deposit any documents in a copyright depository in order to have proof that you wrote that document on a certain date - although in this situation, I don't see why you would do that.
**This post does not constitute legal advice, nor does it create any attorney-client relationship between Sadiq Ansari and any other individual or entity.**
Not really. Copyright protects against copying of works that represent a certain amount of creative expression. That protection covers the expression of your idea(s), but not necessarily an idea itself. What that means is you can secure copyright protection of the actual wording of your business plan, and maybe even the format and layout of the plan if it is unique enough and has some level of creativity. However, this protects only against copying of the words and original diagrams etc. in the plan as you have laid it out--the ideas that you express in the plan are not, per se, protected. Someone can read it and use the ideas expressed in there.
To protect against another party stealing your idea(s), you likely will want to use non-disclosure and confidentiality agreements. This can be very hard to do if you are trying to raise money etc. and another party has leverage and does not want to enter into such an agreement. On a long shot basis, you may have other options as well, especially if your plan regards a method/process that involves a machine that takes subject matter and changes it into something wholly different—in which case it could be worth discussing the idea with a patent attorney, but likely is not worth the capital outlay patents require. Keeping your plan confidential usually is best.
Regardless, copyright will not get you’re the protection you seek.