Ignore "theft" claims because ...

You had an agreement with your (former) friend that he could rent your car out to other
people, so long as he respected some earlier rental/leasing (sort of sharing) agreements that
you'd already worked out with some other friends.

So it's not "theft" inte the sense of larceny.  But it was conversion.

Your (former) friend went and *sold* the car; and when you came back to enforce part of the
agreement vis a vis some of the other friends (IBM) then your former friend sued you for
"slander of title" (claiming that you had sold the car to him --- even though the plain text
of your original, written agreement, specifically excluded the title to the car and
specifically established a fiduciary relationship between your (former) friend and yourself.

Yep!  That's about it.

(Other than the quibbles about the analogies between a single tangible car and the infinitely
duplicatable and modifiable sources in software).


JimD