I encountered something brand new - and wonderfully interesting today:
A buyer is signing a contract for what we call a "new build" - builder doing a new home. This home is going to be a "semi custom" (non tract).
The builder included an addendum to the contract that essentially said, to the buyer, that the builder would use every means possible to assure that no illegal immigrants would be used on the job - that every sub contractor involved in the construction would have to agree to hire ONLY those LEGALLY entitled to work in the United States -
The Buyer happily signed the contract!!