Ask in the Acrobat forum. You’ll get way more help there.
You really don't mean any “OCR in a PDF.” When you export a PDF file from InDesign or otherwise create PDF with text, that text is searchable directly. There is no OCR involved. If the PDF file is available on the web and not behind a “pay wall,” you can expect that search engines will find the PDF file and extract the text for indexing.
The idea of publishing legal notices is that they are public record and thus, somehow prohibiting access to same is very much against the actual legal concept behind a for-the-record legal notice in a publication of record.