>SQLite License. Warranty of title and perpetual right-to-use for the SQLite source code.

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Obtaining A License To Use SQLite

Even though SQLite is in the public domain and does not require a license, some users want to obtain a license anyway. Some reasons for obtaining a license include:

    Your company desires warranty of title and/or indemnity against claims of copyright infringement.
    You are using SQLite in a jurisdiction that does not recognize the public domain.
    You are using SQLite in a jurisdiction that does not recognize the right of an author to dedicate their work to the public domain.
    You want to hold a tangible legal document as evidence that you have the legal right to use and distribute SQLite.
    Your legal department tells you that you have to purchase a license.

If you feel like you really need to purchase a license for SQLite, Hwaci, the company that employs all the developers of SQLite, will sell you one. All proceeds from the sale of SQLite licenses are used to fund continuing improvement and support of SQLite.

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How is it possible that they can sell licenses to the code that was put into the public domain by other contributors?

A contributor must attach the following declaration[1] to contribute. So now their contributions are in public domain. Now in a place where the law doesn't recognize public domain, doesn't the code belong to the original authors? How can an unaffiliated company license it as if they wrote the code?

[1]: "The author or authors of this code dedicate any and all copyright interest in this code to the public domain. We make this dedication for the benefit of the public at large and to the detriment of our heirs and successors. We intend this dedication to be an overt act of relinquishment in perpetuity of all present and future rights to this code under copyright law."