Initially please review an overview of design patents (overview of design patents) and provisional patents (overview of provisional patents).
To determine whether to file a design patent or a provisional/utility patent application it is helpful to understand what your invention is directed towards. If your invention is directed towards novel and new functional features that include a new way of a product working, it is likely that you may want to file a provisional patent application to try to obtain patent protection for these features. If your invention is directed towards a new design of a product or ways items are arranged, it is likely you may want to file a design patent application. However, many times a functional aspect of an invention may be directed towards the arrangement of the novel features on a device. As such, an invention may be protected by both design patents and utility/provisional patents.
When an invention may be covered by both design patent protection and utility patent protection, I recommend the following course of action. First, first a provisional application directed towards the functional aspects of an invention with FIGURES directed towards the design of the application. Second, convert the provisional application to a utility application, which may include any improvements to your invention. Third, once the product is being mass produced/sold, file a design patent claiming priority to the converted utility application (design patents cannot claim priority to provisional applications). Therefore, an invention may be covered by both design patent protection and utility patent protection.
There are many reasons for why I recommend this strategy.
First, by having a pending utility patent application, an inventor may determine if they are able to get broad patent protection on the utility application based on the cited art. If broad claims are granted it may not be required or desired to file a design patent. Yet, if narrow claims are granted or claims that could be determined different, design patent protection may be desired. By filing a utility application, inventors are given an earlier priority date when they may later determine what their intellectual property rights are.
Second, design patents are less costly to obtain and litigate. If design patents are obtained at a later stage, it is likely that your company is still invested in your invention, and the relatively affordable cost to obtain the design patent may be very beneficial. Furthermore, during litigation proceedings it is more efficient and less costly to litigate design patents because there is no claim analysis. During litigation of a design patent it is easier to compare the two designs of products then to determine if the claims are 1) valid, and 2) infringed upon.
Third, by filing a design patent later in the patent process, inventors are likely to know exactly the layout of their manufactured product. By only obtaining design patents on their manufactured products, those that are more likely to be replicated, inventors may limit the costs associated with filing for design patents for each of their designs.
Fourth, the term of design patents are different for utility patents and design patents. The term of design patents is fourteen years from the issue date, while the term for a utility application is twenty years from the filing date of the utility application. Therefore, by filing design patents later in the patent cycle, inventors may be able to extend their patent protection regarding their invention.