The layout is called a mask work because, in photolithographic processes, the multiple etched layers within actual ICs are each created using a mask, called the photomask, to permit or block the light at specific locations, sometimes for hundreds of chips on a wafer simultaneously.
Because of the functional nature of the mask geometry, the designs cannot be effectively protected under copyright law (except perhaps as decorative art).
The Treaty has been incorporated by reference into the TRIPS Agreement of the World Trade Organization (WTO), subject to the following modifications: the term of protection is at least 10 (rather than eight) years from the date of filing an application or of the first commercial exploitation in the world, but Members may provide a term of protection of 15 years from the creation of the layout-design; the exclusive right of the right-holder extends also to articles incorporating integrated circuits in which a protected layout-design is incorporated, in so far as it continues to contain an unlawfully reproduced layout-design; the circumstances in which layout-designs may be used without the consent of right-holders are more restricted; certain acts engaged in unknowingly will not constitute infringement.
Article 35 of TRIPS in Relation to the IPIC Treaty states:[1] Members agree to provide protection to the layout-designs (topographies) of integrated circuits (referred to in this Agreement as "layout-designs") in accordance with Articles 2 through 7 (other than paragraph 3 of Article 6), Article 12 and paragraph 3 of Article 16 of the Treaty on Intellectual Property in Respect of Integrated Circuits and, in addition, to comply with the following provisions.Article 2 of the IPIC Treaty gives the following definitions: (i) 'integrated circuit' means a product, in its final form or an intermediate form, in which the elements, at least one of which is an active element, and some or all of the inter-connections are integrally formed in and/or on a piece of material and which is intended to perform an electronic function, (ii) 'layout-design (topography)' means the three-dimensional disposition, however expressed, of the elements, at least one of which is an active element, and of some or all of the interconnections of an integrated circuit, or such a three-dimensional disposition prepared for an integrated circuit intended for manufacture ...
The non-obligatory symbol used in a mask work protection notice is Ⓜ (M enclosed in a circle; Unicode code point U+24C2/U+1F1AD or HTML numeric character entity Ⓜ/🆭) or *M*.
Similarly, the exclusive right of a patentee to "use" an invention would not prohibit an independently created mask work of identical geometry.
On the other hand, they are used alongside copyright to protect a read-only memory (ROM) component that is encoded to contain computer software.
The publisher of software for a cartridge-based video game console may seek simultaneous protection of its property under several legal constructs: Ordinary copyright law applies to the underlying software (source, binary) and original characters and art.