Hi Michael!
yes, we have recently moved from 11g to 12c as part of a bigger project to move our installations from AOLserver to Naviserver, and from Linux to Windows.
The 12c part was definitely the smoothest part of the project. The only issues we came across were minor:
1. WM_CONCAT function has been removed in 12c - lots of solutions online
2. the 'sync' option to rebuild an index has been removed in 12c - try replacing with EXEC CTX_DLL.SYNC_INDEX( 'cr_rev_content_index' );
3. some internal Oracle views are slower in 12c e.g. USER_CONS_COLUMNS - make sure any joins are also joined by the OWNER column
Happy to help if you have any other queries/concerns.
Brian
