What do I legally do if companies are interested to manufacture my product?

Although you've spent a good deal of money to obtain a patent for a product, which obviously garners significant interest, it is advisable to contact an attorney experienced in negotiating and drafting appropriate business documents such as a licensing agreement. The manufacturers, regardless of any discussion you may have had with them, will look out only for their best interests. They are in business to make money which requires them to manufacture goods at the lowest possible price. As such, you require representation who is looking out for your best interests. To highlight the conflict of interests mentioned, an example using potential licensing agreements can be illustrative. For example, it may be in your best interest to enter a non-exclusive licensing agreement with each manufacturer in order to maximize your potential for profits. However, each manufacturer will likely insist on an exclusive license so that they are the only ones who can manufacture the product. Similarly, you may find that an exclusive license is suitable because other manufacturers are sub-standard in quality or to demonstrate commitment on your part. However, making a determination of any sort requires dedicated evaluation of the circumstances of your situation. Experienced legal representation, although it comes at a cost, can prevent the loss of substantial revenue that you would've otherwise earned with proper agreements in place. Hope this helps!

Congratulations on your success. First, you need to decide which company you want to work with to distribute your product. Next, you need to find an attorney to draft a licensing agreement for you to present to this company and to negotiate the final terms if you aren't comfortable doing that on your own.

Licenses are not easy to negotiate and harder to draft properly. I have extensive experience in both. If you need help please feel free to contact my office.

For all of the reasons you mention prior to the last sentence, enthusiastic or not, you should hire a patent and licensing attorney to resolve these issues for you. The descriptive terminology is "cost of doing business."

Be honest with all three - you have discussed your product with all of them. One option - the highest bidder gets an exclusive license ($$) or can purchase the patent rights from you ($$$). Under an exclusive license - you need minimum yearly royalties - or the license terminates or goes non-exclusive. Another option - all three can have non-exclusive licenses. Many non-exclusive licenses are a paid "up front" variety. You pick a number and they pay once. One & done - you have the $ and they can sell or not sell. Often license fees are "per part" if your product is incorporated into another product; or a "percentage of the sale price." 1-10% range is typical in some cases. Look for sample license agreements on Google. In all such cases - you need a lawyer to help you. Sign NOTHING without checking with your lawyer. Pay NOTHING without checking with your lawyer.