When searching for the "An American in Paris Musical Script PDF Portable," be aware of false positives. The 1951 film script is public domain in some arguments (though the film itself is not), but it is useless for the stage musical.
Always ensure the file explicitly mentions "Book by Craig Lucas" or "Stage Adaptation (2015)" in its metadata.
If you need the script for professional, educational, or personal study purposes, here are your legal options:
Just because you cannot find a free public link does not mean you cannot get a portable version. Here is how professionals do it.
If you need a digital, portable version of An American in Paris for study or production, here are the professional channels: