While this is in play, when you gain a card, you may put that card on top of your deck.
 Official FAQ
- This is a Treasure worth , like Silver.
- If you gain multiple cards with this in play, this applies to each of them - you could put any or all of them on top of your deck.
- If you use this ability and there are no cards left in your deck, you do not shuffle; the card you gained becomes the only card in your deck.
- Royal Seal applies to all cards you gain while it is in play, whether bought or gained other ways.
- If you play the Dominion: Alchemy card Possession, and during the extra turn you have the possessed player play Royal Seal, he cannot put the card on his deck—he is not gaining the card, you are.
 Other Rules clarifications
- If Royal Seal is no longer in play when you gain a card, such as because it was trashed with Mint or top-decked with Mandarin, you cannot use its ability.
 Strategy Article
There is no strategy article for Royal Seal.
There isn't going to be a Royal Seal strategy, but Royal Seal is situationally useful. It's great for Big Money decks which might draw instead of or . It's less useful for engines which probably have better things to buy with than a Silver-equivalent.
- Watchtower does the same thing but is better for engines
 Alternate versions
 In other languages
- Czech: Královská pečeť
- Dutch: Koninklijk zegel
- Finnish: Sinetti (lit. seal)
- French: Sceau royal
- German: Königliches Siegel
- HiG translation error : "... when you gain or buy a card ..."
- ASS translation error : "... when you gain or buy a card ..."
- Italian: Sigillo Reale
- Japanese: 玉璽 (pron. gyokuji)
- Polish: Królewska pieczęć
- Russian: Королевская Печать (pron. korolyevskaya pyechat')
- Spanish: Sello Real
 Secret History