It's the employer's responsibility to monitor inventory, not yours, unless you have the words "loss prevention" in your job title.

And bandwith

This. What if they are already aware of it & waiting for the right time to can his ass. Lying to them isn't a good option.

I would tell but first I would hire an attorney if I were you. The fact you knew this was going on for a while and did nothing may place you in very serious water legally. DO NOT assume thee theft you see your co-worker doing i the only theft he is committing. If he were to get caught and you said nothing he might want to take you down with him (misery loves company). If the amount stolen turns out to be hundreds of thousands of $$$$$$$$ it could be very serious for you. But if you told what you knew in the long run it may be better for you but depending on the seriousness and magnitude of the theft you may still have legal consequences.

Please don't tell on me MTG#10

Just PIIHB when you open in the morning. This way when you both get a light jail sentence together, you'll already have that awkwardness out of the way

I own small businesses. ...Please tell your boss asap.

One thing is for sure I wouldn't invite him to any more cookouts.

That's indeed true.

After HS, it's "rats get bats".

This doesn't count as snitching. You have to worry about your family first.

Loose lips sink ships.

Yup

This

Stupid saying

probably