A google subject search on definite duratioon yielded a ton of stuff. I hit one that cited a case and then looked up that case. I looked up the case in the FSU on-line law library.
City of Homestead v. Beard, 600 So. 2d 450, 453 (Fla.
1992). I found this on Page 8 of a PDF file. Note there was no duration specified, not even a conditional one in the contract apparantely.
"If a period of duration can be inferred from the nature of
a contract and the circumstances surrounding its execution, the
contract is not terminable at will and a court should give effect
to the manifest intent of the parties."
The court in this case cited another case.
In City of Gainesville v. Board of Control, 81 So.2d 5 1 4 (Fla.
1 9 5 5 ) , this Court held that an agreement to furnish water to the
University of Florida without charge, in order to induce the
University to locate in the City, was not terminable at will
despite the lack of a provision as to the duration of the
agreement. The Court held that because the University had
performed under the agreement, the agreement was to remain in
effect until the University left Gainesville.
This can also clue us in as to what constitutes a definite duration. A conditional event such as Until the University left Gainesville or
For the life of the mug indeed appears to be interpreted as being of definite duration in the state of Florida from these even if it is only implied rather than directly specified.
I didn't look up the rules in every state, but in all of them I've spent any length of time in, I see agreements that terminate conditionally upon an event all the time and they seem to be enforced.
Some examples.
These restrictions and covenants shall run with the land unless modified by the association under section blah blah blah until the death of President Ronald Wilson Reagan.
Free oil change for the life of the car, does not include oil and filter.
Free checkups every 15,000 miles, does not include parts and labor for maintenance or repairs.
Free Tire rotation for the life of the tire.
.