We can use properties to set Adobe Acrobat not to take ownership of the default PDF file extension, by leaving Adobe Reader as the default PDF reader.

For version 10.0 & higher use the property LEAVE_PDFOWNERSHIP=YES

YES - prevents the new installation from taking over PDF ownership. 
NO - allows the new install to own opening PDFs. 

For version 11.0 & higher use the property OWNERSHIP_STATE=0.

0: Do not take ownership.
1: Take ownership for the current user. 
2: Take ownership for all existing and new users.