Yes, it technically merged with Wendy's, but is now a subsidiary. So basically, to save face, it merged, and was not bought out. It's now a wholly-owned subsidiary of Wendy's, though run separately.
From
http://www.timhortons.com/en/about/faq.html#three
"Tim Hortons merged with Wendy’s International, Inc. in 1995. While we are a wholly owned subsidiary of Wendy’s, the Tim Hortons chain is still run completely separately from our head office in Oakville, Ontario, Canada."
Whatever, though. Potato, schmotato. It'll always be "Canada" to me