Don't bother applying. TR is making so many cuts and selling off parts of the company it's difficult to keep track of what department is staying or getting outsourced. Apply somewhere else. The mood in Toronto office is grim.
The culture is hard to define as the company operates in so many countries and has so many companies under it, some of which compete against each other for the same customers. In the office where I worked, you had different departments that would not work together and the division between Reuters, Thomson and Bridge people were pretty evident at the start. Many people work from home, so it is hard to get to know who to speak with without going first through your manager that likely worked in another country.
Everything via email - only face to face when requested by you. Management is hands off on guidance, feedback, criticism, etc unless provoked.
If you were in charge, what would you do to make Thomson Reuters a better place to work?
I would put up an area where mothers can leave their kids to play while they work.
As a freelance instructor for TR, the working hours varied from course to course. but on average, it was 10am to 6/7pm with an hour for the students to have lunch