Related Clues:

• Licence for invention; obvious
• Licence for invention
• Register (an invention)
• Old bishop opposed to promises of redemption, it's clear
• Having stroke at hospital department is unmistakeable
• Inventor's licence
• Readily seen
• Licence for inventors; obvious
• It's obvious to father providing temporary accommodation
• Obvious safeguard for inventor
• Obvious way to protect one's invention
• The answer is obvious. Protect it by law
• Died with few debts, as is evident
• It's leather, that's obvious
• Manifest - an official document