Looking for the movie title of a thriller from the 1970ies

Hello movie fans,

I have been looking for a Thriller film from the 1970ies (or 1980ies).
So my memory may be off in some aspects but this is what I think I remember

The protagonist is an engineer or a mathematician who possesses some valuable information (formula, or equation). He is chased by some larger entity, a company, or a group of men, who want that information.
I also remember that there is a woman who helps him throughout the movie.
I also remember that it ends with the protagonist getting on a boat or ferry to flee from the situation, an act that was arranged by that woman.

I would appreciate all kids of hints or guesses or the title.

Thanks!!!