Software Copyright is the most common method used to protect a software. A programmer automatically owns the copyright of any program they write (it does not need to be applied for) and it lasts until 70 years after the death of the author.
Copyright does not protect facts, ideas, systems, or methods of operation, but instead protects the way that these things are expressed. You can outline your ideas in writing or drawings, but a copyright cannot protect the idea itself. Instead, it protects fixed, tangible mediums of expression that can be reproduced, i.e. the final written or artistic work.
Historically, computer programs were not protected by copyright because until 1974 computer programs were not viewed as fixed, tangible objects. However, in 1983 traditional copyright law was extended to include machine-readable software and the Copyright Act awarded computer programs the same copyright status as literary works. While many of the same legal principles and policies apply, there are a number of distinct issues that arise with software copyright.
When you run a program on a computer it is often impossible to avoid copying some of the code as there is normally some automatic copying of the program that takes place within the computer’s memory in order to enable the software to function. Also uniquely with software, copyright is not only infringed by taking a direct copy of the original work, but also by adapting versions of the original. So for example, if the code (source code or compiled code) is re-written or otherwise converted into another computer language, this is also deemed an infringement of software copyright law as it is a ‘derivative’ work, and an appropriate licence is required to do this. Software copyright can also be infringed without even taking a copy of the code. For example, using an original computer program for “inspiration”, to create the same functionality in a new program. Even if none of the original code is actually used, the copyright in the original program may in some cases be infringed. Software copyright is a complex and evolving area of law and unlike other artistic works, software copies are sold with specific terms attached, in order to highlight what constitutes acceptable usage.
Software copyright is predominantly used by software developers and proprietary software owners to prevent unauthorized copying of their software. The copyright holder is typically the work’s creator, or a publisher or other business to whom copyright has been assigned. Copyright holders routinely invoke legal and technological measures to prevent and penalize copyright infringement (more commonly referred to as piracy) where works protected by copyright law are used without permission. For works such as software and web applications, the source code is primarily where copyright exists and a copyright notice should be inserted in the headers of all source code files, help files, user manuals and/or ‘about this software’ pages, to make the assertion of copyright explicit.
Where there is no direct copying of code, line-for-line, it can be difficult to prove that copying has actually occurred. One way of trying to make copying easier to detect is to include redundant code or program components in among the real code. If an alleged copy includes the same redundant program components, even if they are not line-for-line copies, it can provide a very strong inference that copying has occurred.
Independent software vendors should be very careful about disclosing source code. If someone can independently create from scratch what you have produced, just by looking at your source code, providing that the code is substantively different then your software copyright has not been infringed. The modification of your copyrighted software for personal use may also be deemed acceptable under the caveat of ‘fair use’ and also code breaking and reverse engineering when a ‘legitimate reason’ can be provided for doing so. However ultimately any unauthorized use of the software is deemed to be piracy or theft, in recognition of the commercial harm of infringement of copyright holders.