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Don't tell me that I can't. Tell me how I can.
Disclaimer:   I am not a spokesperson for the US Coast Guard or ABYC. For an official interpretation of regulations or standards you must contact the US Coast Guard or other organization referenced..   More.....

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Running a boat building business involves legal issues such as model year, and copying your products.

Model Year: This has been much discussed by boat manufacturers, dealers, and engine manufacturers as well as by the Coast Guard and the States.

As far as I am aware the only law requiring a model year designation is the regulation on;

Hull Identification Number .

Most boat manufacturers give their boats a model year and make changes to their model lines every year.  However, small businesses generally don't make many changes from year to year and some never change their boats except to make improvements that are necessary. Most often these changes are not obvious and are in the actual structure rather than the appearance of the boat. So these builders often don't want to declare a model year. There are even some large boat builders who do this. Grand Banks rarely makes changes to their boats and a 1990 looks exactly like a 2000. They have in the past objected to putting a model year on their boats. So why use model year?

First is your customer.  Customers like to know when a boat is new, or not. They like to know  what model year it is.  Model Year is not terribly important if you never change the boat, but if you make changes then it is.

Second, most states require a model year on the registration. But, this model year is taken right from the Hull Identification Number.

Recently engine manufacturers have been discussing not using a model year. Mainly this is so boat dealers can put a engine on a boat without worrying about whether the engine is the same model year as the boat, as long as it is new. However, the serial number of the engine would still be able to reveal the year of manufacture so there would be no confusion over parts numbers.  A new model would be manufactured when a major change was made to the engine. This may work for engines but it is not as practical for boats.

The biggest problem with model year is a sales and inventory problem. If you have a boat in inventory from last year, and it has never been sold, is it a "New" boat or is it last years model?  The HIN law says that you can't change the HIN once the boat enters interstate commerce.  This means when it has been sold, or shipped to a dealer.  But as long as it is still at the factory the builder is free to put whatever model year in the HIN that they wish. However, this can run into a problem with state registration if the model year is more than one year removed from the date of manufacture. So be cautious if you do this.  After the boat leaves the factory, it becomes illegal to change the model year.  A dealer, manufacturer or anyone else CAN NOT change a Hull Identification Number to update the model year no matter how long the boat sits on his lot. The Federal regulation requires that permission be obtained from the Coast Guard to make any alteration to the HIN.  Also, a dealer or seller cannot misrepresent an older model as a current model year boat because most states would consider this consumer fraud.  They can however state that it is a "New" boat as long as this is true.

When does  a model year begin or end? As of 2009 the US Coast Guard began enforcing the model year regulation as it is written:

Model year means the period beginning August 1 of any year and ending on July 31 of the following year. Each model year is designated by the year in which it ends. Title 33 Code Of Federal Regulations Chapter I Part 181.3.

So Model year begins on August 1st and ends on July 31.  Example: Model Year 2012 would begin August 1, 2011, and end July 31, 2012.

Prior to this the US Coast Guard had been allowing manufacturers to determine the model year. So older boats may have a different model year span than new boats.  But new boats must use the definition as stated above.  For the rules, go to the page on


Splashing, or copying someone else's boat. Most people believe they have the sole rights to the use of their own creations or ideas. This is true to some extent. However, it is also known that many people get started in the boat building business by simply copying someone else's design. In the USA this is called "splashing", in Europe it is often referred to as "flopping". This is a very common practice. Sometimes this is perfectly legal but most times it is not.  It depends on the laws in your state, copyright and trademark laws, and a Federal Law called the Vessel Hull Design Protection Act. It also depends on the nature of the design that is copied.  I will try to keep this as simple as possible because the issue can become very complex. Sometimes only the courts can sort it out. As I said in my disclaimer, I am not an attorney, I am an engineer. So I will try to keep it in engineering terms.  But if you have questions about this I suggest you contact an attorney that specializes in copyright, trademark and patent laws.

Basically, you cannot splash or copy someone else's design  of an existing boat without their permission, or unless it is in the public domain.  Splashing means making a mold from someone else's boat. Some people think that if the boat design is changed a little bit, then copying or splashing  is legal.  This is not true. You can still be sued by the designer and lose. This also includes copying someone else's design from plans or drawings.

Legitimate use of someone else's design.  What is public domain? When is someone else's design in the public domain?   Public domain means anyone can legally use it for private or commercial use. One way a design becomes public domain is if the creator of the design says it is. They do this by publishing  and encouraging others to use their design. There are literally thousands of wooden boat designs that fall into this category and many sail and powerboat designs  are in the public domain. However, the act of publishing  alone does not make it public domain.  It has to include the intent by the creator to make it available for anyone to use.

Some designs have been around so long that no one can legitimately claim ownership, such as the dory, or jon boat.  No one could legitimately say the idea of a dory or jon boat is theirs because these types of boats have been constructed for several hundred years by many boat builders . The design of a simple vee bottom outboard boat is so basic that no one can claim ownership. Vee bottom planing hull boats have been around since the early 1900's.  Canoes are essentially in the public domain because canoes have been made since prehistoric times. Catamarans have been built since prehistoric times in the South Pacific. Basic simple hull designs are almost always public domain.

On the other hand, the unique Boston Whaler design of a cathedral type hull is owned by Boston Whaler.  The hull shape is not necessarily new but they way they put it all together is unique.  A few companies  have tried to copy it but  Boston Whaler has defended their ownership of this design in court and won.  So if you see a nice boat and think it would be a good idea just to take a mold off the hull you may be breaking the law.  This is not a criminal offense, that is, you won't be jailed or fined. But it is civil offence, and you can be sued and have to pay the owner. This means paying them the proceeds you got from selling all of the boats you made with this design, and destroying the molds, plans, templates, or any other patterns used to make this boat.

None of the above prohibits you from improving on a design if it is a genuine improvement. If you see a boat and think it would be better if it had less dead rise aft or a bigger transom, or steps on the planing surface, you can make those types of changes.  Many basic hull shapes have been around for a hundred years and are being constantly "improved". A good example is the first Bertram, Moppie.  Deep vee boats had been around for a long time, but Bertram carried the vee at the same angle of deadrise all the way forward to the stem and added lifting strakes at intervals on the hull. Up until then no one else had done this.

There is nothing illegal about this type of improvement of an existing commonly used design. But, beware, some designers have taken others to court for building a boat so similar to theirs that it could be reasonably mistaken for their design.  This is the look and feel issue.  If it looks like and feels like their design, it probably is.

There have been cases where people have defended themselves against such law suits by showing the history of a hull design. They show how small changes have been made to it over many, many years and how their variation fits in and is different from that of the person suing them. They also show that the design of the person suing them is just another variation on a design that has existed for many years.  Sometimes this works, sometimes it doesn't.

Coming up with a design independently, that is, by your own  creative work, without having access to or having seen the other boat that it resembles, does not necessarily violate someone else's right to the design.  But you may have to prove that you developed the design on your own.  This can only be decided by the courts.

Illegal use of someone else's design: This means simply copying someone else's design and selling it as your own. It doesn't matter how it was copied, whether by using plans or splashing a mold. You must have permission from the "owner" of the design to copy it. This is seldom given without some consideration in return, that is, paying them for the right to use it.

Vessel Hull Design Protection Act. A US Federal law was passed in 1998 as an attempt to stop all  the splashing and copying that occurs in the boat building business.  It states that a designer or builder can register their hull design with the Trademark and Patent Office. Once it has been registered, no one can copy the design.  This is not the same as a patent or a copyright but in effect makes the designer or builder the "owner" of the design. To get this protection, a designer or builder must register their design. Approval is not automatic. The Trademark and Patent Office will do a search of the other registered hull designs and patents to make sure this design hasn't already been registered or patented. If it already exists as a registered or patented design then it will not be given registration. This does provide the creator of a design with some protection.  In 2005 amendments were added to strengthen the law.  
The Act .

The Act Overview and analysis.

This law is also enforceable in the courts in other countries through treaties the USA has with those countries under general patent and copyright infringement agreements.  However this could be very expensive to prosecute. That still doesn't mean you can copy someone else's design just because they are in another country. It is still stealing.

Here are some papers on this subject.  It is full of legal jargon and references to laws and court cases but it is clear enough for anyone to understand the point of it all.
Outrigger Hull Design Protection

Here are some other papers on this subject.
Two Perspectives On The Vessel Hull Design Protection Act

Florida IP Trends: Vessel Hull Design Protection Act - What The Hull?

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American Boat And Yacht Council  Boat Design Net  Wooden Boat Foundation
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