These blog articles are less about actual locking mailboxes and more about the process of product development, at least whay I have learned about product development through the process of doing these mailboxes.

You are almost never going to be able to do any kind of product development without having to take into account the intellectual property that may exist on other products that are like yours.  There are almost no totally new products in the world.  Most products are modifications of existing products, with most of those having some kind of intellectual property associated with them.  

Patent law is tricky and complex.  If you look at a product, and you see that it lists a patent with the patent number, then it is a pretty easy thing to go to the US Patent and Trademark Office to look up the published patent.  The basis of patents are what are called claims.  A person can make any type of claim they want in a patent application, however, there has to be at least one original claim in the patent, one new thing that nobody has ever seen or invented before.  Also, patent drafters make claims as broad as possible.  For example instead of saying "part A is attached to part B by a screw"  you would say "part A is attached to part B by a fastening means (or means of fastening).  That way somebody can't come and violate your patent by saying "hey...I didn't use a screw..I used a nail instead."

Anyway, back to original claims.  So you make a series of claims for your invention, with at least one claim being completely original.  For example...for my invention of a disappearing pencil I would say something to the effect "I claim an invention comprised of a wood like cylinder that is hollow inside, with the interior of the hollow part containing a solid carbon substance,  with said wood like cylinder and carbon interior possessing the property of not being visible when a sharp noise making means is activated."

In this example, I claimed that I invented a pencil, and my claims spelled out a basic pencil.  Well, the pencil has been around for decades.  I did not invent the pencil.  What I'm really claiming is that I invented a pencil...that everybody already knows about...but the pencil that I invented has one additional quality that nobody has every seen before in a pencil.  That quality is that this pencil can disappear from view when I clap my hands really loud (or make any other sharp noise). 

So my claim contains elements a) wooden cylinder b) hollow inside c)inside filled with carbon d) pencil can disappear when a sharp noise is made.  If somebody else tries to copy my invention, and it contains all of elements a,b,c, and d, then they have violated my patent.  However, if they just make something that contains elements a,b, and c, then there is no violation even though I have those in my claims.  Any claims that I make that already exist are what is know as prior art.  If somebody made a pencil,  but without the disappearing feature, then they have not violated my patent.  Even if their pencil looks exactly like mine there is still no violation because these types of pencils have already been around for decades and these known types of pencils have become part of the prior art.  As long as it does not contain the disappearing feature, then there is no violation.

Somebody could make a pencil that contains a,b,c, but not d, but maybe they add some other element, e.  If this knew element e was totally original and unknown as applied to pencils..then that new individual could file a patent on the basis of his new element e.

For example...maybe the new person made a pencil that could fly.  He would not violate my patent.  Now, if he invented a pencil that could fly and was invisible when you clapped your hands...then there is a violation.

Clear as mud..right?  Anyway, when evaluating whether or not the product you want to make is violating the patent of another similar product, you will need to become very familiar with the patent in question and with all the products like the product in question that have existed before.  The first step is to make sure your new product is not violating another patent.  If in the process of this, you make an improvement to the product, then the next step is to see if you can get a patent on your improvement.  To do that you will have to make sure that nobody else thought of the improvement before you.  If they did, then it is prior art and you did not really invent it and therefore could not get a patent on it.  

Of these two steps, the most important step is to make sure you are not violating the other patent.  This step can be problematic because when you are looking at a series of elements in a claim on a patent, you can never quite be sure which of the elements is the original element.  The patent itself does not spell it out...it does not say in bold red letters "and now, for the original element......"  That would be too easy.  You could see what the original element was, and then you could copy their product exactly, minus the element you know to be original.

When examining the patent, you have to try to figure out which elements of the claim are already known in the prior art, and which ones are original.  In the pencil example above, it was easy.  Everybody knows about the pencil, yet nobody has seen a disappearing pencil.  So it is obvious that the wooden cylinder with the carbon inside are the claims that are contained in the prior art, and the disappearing feature is the new element.  However, in the case of the nifty can opener I saw at Bed Bath and Beyond last week, you can't really be sure which element is original and which is not.  You have to do a lot of research to figure out which elements of the can opener claimed in the patent have been around before this product came to market, and which ones are original to this product.

Often times, the patent office will grant patents on original elements that almost seem ridiculous becasue they are so simple.  Like, in the example of the new can opener I saw, maybe the blade is oriented a different way than ever before on can openers.  That can be enough different of an element to get a patent.  If you can figure out which element is original, and if the original element was almost ridiculous in nature and really did not affect the functionality of the product, you could keep almost 100% of the functionality of the product but still eliminate the original element, then you could virtually copy a product exactly and not violate the patent (you might violate other IP law, but not the patent itself, more on this later).

So the key is to do enough research on the product in question that you can establish which elements of the patent are original, and which are known in the prior art.  Then you make sure your product does not contain the original element.  You do this by scouring old patent applications, and if it is a fairly common thing (like a pencil or a can opener) look at all the products like it you can find anywhere (home stores, your kitchen, etc) and examine them to see if the elements they contain are the same elements in the patent.  Furthermore, in this process you might discover something new and original, and maybe you get a patent on that.