Where did he say he anyone was rehired as a W-2 contractor? 1099 could be possible (except for the whole work-for-hire IP issue).
The IRS looks at the common law rules between the two entities, based on three categories:
Behavioral: http://www.irs.gov/businesses/small/article/0,,id=179111,00....
Financial: http://www.irs.gov/businesses/small/article/0,,id=179113,00....
Type of Relationship: http://www.irs.gov/businesses/small/article/0,,id=179116,00....
There is even an IRS form, SS-8, which you can submit to the IRS to 'clarify' how the relationship should be treated...
http://www.irs.gov/pub/irs-pdf/fss8.pdf
All of this information is available here:
http://www.irs.gov/businesses/small/article/0,,id=99921,00.h...