This is the 1827th most frequent Swedish word.
hemligstämplade
Classified or secret-stamped.
Here, 'hemligstämplade' is used as an adjective describing the documents, meaning they are officially marked as confidential.
Dokumenten som hittades var hemligstämplade.
The documents that were found were classified.
In this sentence, 'hemligstämplade' is the verb form, indicating the action of declaring the report confidential.
Han hemligstämplade rapporten innan den delades med andra.
He classified the report before sharing it with others.
'Hemligstämplade' functions as an adjective, describing the documents which are designated as confidential.