Yes, usually a light digital watermark with your name and purchase date. This prevents sharing. If you download a "free" PDF with no watermark, it is an illegal scan.
A companion volume available in over 14 languages (including English, Russian, and German). It provides vocabulary lists, grammar explanations, and translations for the dialogues in the main book. 2. Level Breakdown Minna No Nihongo Elementary 1-2 Main Textbook Pdf