Most, if not all, of LRH and Scientology writings are copyrighted. Not merely by virtue of having been written, and having a copyright notice appended, but also by virtue of having been registered with the U.S. Copyright Office. This applies to translated works as well as the original English ones.
The U.S. Copyright Office has online search facilities, and one can search for any title by name, or any individual or company/organization by name to see if that person or entity is registered as having claimed the copyright to any titles.
An example of a full entry is:
Registered Works Database (Author Search) HUBBARD, L. RON (3,523 items) 1. Registration Number: RE-3-635 Title: Child dianetics. By L. Ron Hubbard. Claimant: L. Ron Hubbard (A) Effective Registration Date: 22May78 Original Registration Date: 23Dec50; Original Registration Number: AA178150. Original Class: A
Note that there is also a database of copyright transfers. An entry in this might involve the transfer of several thousand titles, the details of which are not available in the online search although the details probably would be available in a personal visit to the public records at the Library of Congress. So the record of the original claim is not necessarily a statement of the current copyright owner/claimant.
An example of a transfer record is:
ITEM 47 OF 334 SET 11: BRIEF DISPLAY FILE: COHD (ASCENDING ORDER) V3058 P155 THRU 164 (COHD) RECORDED: 29Nov94 EXECUTED: 18Nov94 PARTY 1: Mary Sue Hubbard, widow, Diana Meredith Dewolf Hubbard Ryan, Mary Suzette Rochelle Hubbard, Arthur Ronald Conway Hubbard, Lafayette Ronald Conway Hubbard , Jr. a.k.a. L. Ron Hubbard , Jr. a.k.a. Nibs Hubbard a.k.a. Ronald Dewolf & Katherine May Hubbard Gillespie, children of deceased author, L. Ron Hubbard, by Church of Spiritual Technology (Atty) PARTY 2: Church of Spiritual Technology (Los Angeles) NOTE: Ceremonies of the Founding Church of Scientology & 1,364 other titles. By L. Ron Hubbard. Copyright assignment. FULL DOCUMENT RANGE: (In V3058 P155-208)