The license states this project is placed in the public domain, however
the license includes a restriction on certain uses of the software,
which would seem to make this a license, not a true public domain
Blat Public Domain License Version 2.0
The authors of Blat have placed it in the public domain. This means you can use it free of charge for any purpose you like, with nearly no
conditions being placed on its use by us. The source code is also available free of charge and under the same conditions as the executables.
You have permission to modify, redistribute, hoard, or even sell Blat in its executable or source form. If you do sell Blat, though, we'd
appreciate it if you'd provide your own support (and send us a free copy). We cannot take any support load for Blat (we've got better things to do).
The only limitation we impose is that Blat not be used to send unsolicited commercial eMail (UCE). Use of this software to send
unsolicited commercial eMail constitutes an agreement to pay each of the authors $10,000.
Various bits of the source code are copyright by other people/organizations. Look in the source code for copyright ownership.
The authors and contributors of the package are not responsible for any damage or losses that the usage of Blat may cause. We are especially not
responsible for the misuse of the SMTP (or other) mail system.