Related Clues:

• Dripped from the pipe
• Was unable to keep a secret
• Disclosed, as secret data
• Emulated a rat
• Was a ratfink
• Didn't keep mum
• Gave the game away
• Notified
• "I ___ you so!"
• Didn't hold water
• Imparted
• "__ you!"
• Let in on
• Took effect
• Sang like a canary, so to speak