The AutoCAD Help file states that if you add a password to a drawing, no program can read the drawing without the password, and if you lose the password its not recoverable, so that approach may not meet your need. I'm just offering a caution in case you decide to explore that approach.
SO- lets look at your posted need. Your vendor requires an original DWG to simplify their inspection. What your post implies is that they can't read the information they need to do their inspection from the face of the drawing as they view it, which they could do by viewing the PDF of your drawing.
1. Password protecting the drawing may make it unreadable without the password, and providing the vendor with the password so they can read the file just re-opens the availability of the data in an "unlocked" fashion, so that may not be the answer. I'd still look into this because it does address a portability issue where confidentiality is concerned, and may be useful in other situations even if it doesn't help here.
2. Providing the basic drawing file (DWG) in an unlocked fashion defeats your need for drawing "security".
3. Providing a password protected PDF, while augmenting the security to a desired level, provides the vendor with visual access only, again not meeting the need.
4. Providing the vendor with a non-password protected PDF of the drawing defeats drawing security because a vendor (any vendor, not NECESSARILY this one - in keeping with the spirit of your initial concern) who wishes, can backward-translate the PDF into a DWG which they could then use in just the manner you do not wish.
Your only answer might be to extract just what the vendor needs to fulfill their responsibilities to your company under your contract, and provide that information to them. I'd get the advice of your legal department tho, on matters having to do with confidentiality !
Still, if your relationship with your vendor is a good one, all of this may not necessarily apply. However a good philosophy might include the notion that locks tend to keep out honest people. Your legal department might need to provide the level of security you're seeking, if a password won't.
Ok- good luck ! And post back here with any results to your initial query?
Tks-
-C.
If anyone else can think of a fool-proof way to lock down the data yet still make it open for use, I'm sure redpicker would be very interested ! Actually, so would I !
