Recourse against a temporary worker that benefited, to the detriment of our company, from knowledge gained at our client

Normally, an employer does not keep the fact it is going to hire confidential -- otherwise it could not fill the position. The fact your client was going to hire would not be confidential and the clause you refer to in your question, at least in isolation, does not appear to be much help to you. You should consult with an attorney to discuss the particulars of the matter, to have your contract reviewed and for any specific legal advice.

Your issue is not so much with the employee who took the job with the client. You should have had a provision in your contract with the client that prevents them from hiring people you place with them for a specified period of time, along with a penalty clause if they do. If your contracts do have these type of provisions, consult with an attorney in your area to review what stapes can be taken to enforce the contract.

If you have a contract with the client which prohibits it from hiring temps you provide, you would have a breach of contract claim against the client.

If you have no such provision in your contract, or you have no contract at all, you could possibly have a claim against the client for interfering with your contract with the employee who you placed.

Interefrence with contract requires knowledge of the contract, and an intent to interfere with or disrupt it.

You might also have a breach of contract claim against the placed employee based upon the provision you cite.

I would have to see how "Confidentail Information" is defined to give you a better read on such a claim.

I would strongly suggest you consult with an attorney with respect to this matter.

You should also have the attorney review the form of contracts you use to make sure you are protected from this type of situation in the future.

I would strongly urge you to consult immediately with a litigator skilled in this area of the law.

PLEASE NOTE THAT THIS RESPONSE SHOULD NOT BE CONSTRUED AS A LEGAL OPINION OR ADVISE, AND DOES NOT CREATE AN ATTORNEY-CLIENT RELATIONSHIP. IN ORDER TO RENDER A LEGAL OPINION OR ADVISE, THE RESPONDING ATTORNEY WOULD NEED FAR MORE INFORMATION THAN HAS BEEN PROVIDED, AND WOULD NEED TO BE RETAINED PURSUANT TO A WRITTEN FEE AGREEMENT.