I have an international flight tomorrow on Air Canada. My flight originates in the U.S. and has a connection in Toronto to a foreign destination.

I have two boarding passes - one is for my U.S. to Toronto portion of the trip and the second boarding pass is from Toronto to the foreign destination.

My boarding pass for the U.S. portion of the trip is marked with TSA Pre check.

My question is related to the second boarding pass. In the place on the boarding pass where the TSA would be shown, instead there are three letters -
OSS.

Does anyone have a clue what the OSS designation represents?

-