English to German Law/Patents Law: Contract(s)

I have seen this phrase quite frequently and always gotten away with a free translation. However, I suspect that there might be a German equivalent to this expression, which usually appears in phrases like "..the testimony was reduced to writing and authenticated... ".

Here is the sentence:

"A and X desire to reduce their understanding to writing in order to insure that trade secrets of A are fully protected."

So far, I have structured my translations around "schriftlich darlegen". Is there a specific German legal phrase?

Thanks for your help,
Ursula