Requirements vary depending on the version, so check required
In case of duplicate use, redistribution may vary depending on compatibility. Recently, Artifex Software, an American software company, filed a copyright infringement lawsuit against Hangul & Computer for violation of open source license. The problem was that Artifex's GhostScript was embedded in Hancom Office.
Open source software is easy to think of as free because it is open to developers so that anyone can use, copy, modify, and redistribute the source code. However, open source SW is SW that is protected by intellectual property rights (IP), not just open source code. If you are going to use open source, you need to check how much it is 'open'.
Ghostscript, licensed under the GNU AGPL, is a software for PDF page description language. Recently, Artifex filed a copyright infringement lawsuit against Hangul and Computer.
Open source has more than 80 licensing obligations, including obligations to disclose source code, obligations to notify copyrights, obligations to waive patents, and obligations to notify usage rights. Representative licenses among those certified by OSI, an organization that certifies open source licenses (copyrights), include AL (Apache License), BSD (Berkeley Software Distribution), GPL (General Public License), LGPL (Lesser General Public License), MIT, and MPL (Mozilla Public License). Even if the names are the same, the details of the obligations differ depending on the version, so confirmation is essential.
When using it internally, you do not have to follow the obligations, but when you physically distribute or sell it, you have to follow various obligations. In the case of GPL, software that links or includes the source code is obligated to be disclosed to all code recipients. Here, the recipient is the person who receives the contract and the product and can redistribute it free of charge. However, there is no obligation to distribute it to an unspecified number of public.
For example, if a university makes an academic management system open source and distributes the app to students, it may be considered internal use from the university's perspective, but students are included as external parties. Students have the right to request that the app's source code be disclosed.
Comparing the features of major open source licenses
Common requirements for open source SW licenses include copyright notice, license copy inclusion, warranty disclaimer, limitation of liability, return of source code, and patent provisions. If a company wants to commercialize with open source, it should pay attention to the obligation to return source code and copyright notice among these.
AGPL, GPL, LGPL, MPL, EPL, etc. require the return of source code. The source code of the SW that is linked or includes the code must be disclosed, and non-public SW can be changed to public SW. There is a possibility that patents, trade secrets, core technologies, etc. may be leaked to the outside, so caution is required. The copyright notification obligation guarantees legal rights under copyright law, and if it is not complied with in the public SW license, there is a possibility of legal disputes.
Another thing to note is the compatibility of licenses. When using multiple open sources, distribution is not possible just by specifying the license. There are open source SWs that can be used together, and there are SWs that cannot be distributed externally when used together. When distributing, you need to check if the open source SWs conflict. For example, GPL2.0 and AL2.0 cannot be redistributed together because their license requirements conflict. On the other hand, GPL3.0 and AL2.0 can be used together.
The next thing to consider before commercialization is whether to use a multi-license or a hybrid license. A multi-license is to distribute two or more SWs with different terms and conditions. If you create a proprietary application, you can choose a proprietary license, and if you create a copyleft application, you can choose free SW. You can make a profit by distributing the free SW version for free and providing an advertising license to the corporation.
Compatibility between GNU GPL family licenses
Hybrid license provides the basic program as a community version, and sells additional functions commercially in the form of modules/libraries. It has a business model that generates revenue by selling enterprise versions with additional features.
The National IT Industry Promotion Agency (NIPA) provides a free open source SW license verification service for small and medium-sized businesses. It searches the code developed by the company, verifies which license was used, and writes a report.
Park Jun-seok, a senior at the SW Competency Plaza of the National IT Industry Promotion Agency, said, “For commercial SW, the company that makes it takes full responsibility, but for open source SW, the user must take responsibility.” He pointed out, “By 2019, 99% of people will use open source SW. Half of them are not managing it. In Korea in particular, management is neglected due to cost.”
