Protection of a computer manufacturer's laptop design would be considered an example of a:

A patent protects new and useful inventions, which can include the unique industrial design (design patent) or the functional processes and components (utility patent) of a computer manufacturer's laptop. This grants the inventor exclusive rights for a limited period, preventing others from making, using, or selling the invention without permission.

A watermark is a faint design or mark used to identify or protect ownership of digital or physical documents, not the design of a product itself.

Copyright protects original literary, dramatic, musical, and artistic works, such as software code, user manuals, or marketing materials for the laptop, but typically not the physical design of the product.

A trademark protects words, phrases, symbols, or designs that identify and distinguish the source of goods of one party from those of others, such as the company logo or brand name, not the laptop's industrial design.