temp worker work made for hire?

Hi, gang,

Anyone know of any law regarding the ownership of works created by employees of a temp agency (e.g., Manpower, or Kelly) who create works of authorship while engaged through the temp agency?

Example: Helen is employed by Manpower, which sends her to various clients of Manpower to do temporary admin (secretarial) work. (Helen is in fact a talented programmer, but was looking for something "different" to do for awhile.) Helen is paid by Manpower; Manpower deducts social security, tax withholdings, etc. Helen does administrative work, but discovers while working at one particular client of Manpower that she can make her tasks go faster by writing a little program to automate them, which she does, on the company's time, and on the company's computer system. Her supervisor, impressed by the speed at which she is accomplishing her tasks, asks how she does it, and she shows him the program.

The temporary "employer" then circulates Helen's program throughout its organization, where it helps hundreds of other admins.

Assuming no written agreement (either between Helen and the temp agency, or between the temp agency and the temporary "employer") covering anything remotely related to intellectual property, who owns Helen's work? Helen? The temp agency? The temporary "employer"? Does the temporary "employer" have shop rights?

-Ari

Ari Kahan
<akahan[_at_]netcom.com>