Software companies often enter into specific agreements with large companies and public authorities, which include specially designed support contracts and guarantees. A free software license gives users of this software the right to use, modify and redistribute creative works and software that are both copyrighted and generally not licensed with proprietary software. These licenses usually contain a disclaimer, but this feature is not just for free software.  Copyleft licenses also contain a key add-on clause, which must be followed to copy or modify the software, requiring the user to provide source code to the factory and distribute its changes under the same license (or sometimes compatible); effectively to protect derivative works from the loss of original permissions used in proprietary programs. Most retail software licenses reject (as far as local laws permit) any guarantee on the performance of the software and limit liability in case of damage to the purchase price of the software. One known case that confirmed such a disclaimer is Mortenson v. Timberline. Recently, publishers have begun encrypting their software packages to prevent the user from installing the software without accepting the license agreement or violating the Digital Millennium Copyright Act (DMCA) and foreign counterparts. [Citation required] End-user licensing agreements are usually lengthy and written in very specific legal language, making it more difficult for the average user to give informed consent.  When the company designs the end-user licensing agreement in such a way as to deliberately deter users from reading it and is difficult to understand, many users may not give their informed consent. An end-user license agreement (EULA, /-ju-l/) is a legal contract between a software developer or provider and the user of the software, often acquired by the user through an intermediary such as a distributor.
A Board defines in detail the rights and restrictions applicable to the use of the software.  In addition, in ProCD v. Zeidenberg, the license was declared enforceable because it was necessary for the customer to accept the terms of the agreement by clicking a “I agree” button to install the software. However, in Specht v. Netscape Communications Corp., the licensee was able to download and install the software without having to review the terms of the agreement and approve it positively, so that the license is considered unenforceable. The term narrow wrap license commonly refers to any software licensing agreement that is included in software and is not accessible to the customer until after purchase. As a general rule, the license agreement is printed on paper contained in the boxed software. It can also be displayed on the screen during the user`s installation, in which case the license is sometimes called the Click-Wrap license. The client`s inability to verify the license agreement prior to the purchase of the software has led to the absence of legal difficulties in some cases.