This is the 9995th most frequent Polish word.
autorskie
"Autorskie" means "authorial" or "pertaining to the author."
Here, 'autorskie' is used in the plural dative form belonging to the noun phrase 'prawami autorskimi' meaning 'copyright rights'. It denotes that the book is under the author's rights.
Książka jest objęta prawami autorskimi.
The book is copyrighted.
In this sentence, 'autorski' is used as an adjective and means 'authorial', referring to the distinctive manner that reflects the author's or creator's unique contributions.
Ten film ma wyjątkowy styl autorski.
This film has a unique authorial style.
Here, 'autorskie' is an adjective describing 'oprogramowanie' (software) as proprietary, indicating that it is uniquely created or custom-designed by the creators.