If I prepare a provisional application for a, say, disk holder. The descriptions, drawings, etc. indicate a rack with 10 slots for disks. After receiving the pending patent status, can I add or substract slots in the patent app. which do not affect the concept of the invention?
Provisionals are not reviewed for grants, but merely establish an earlier priority date for the invention in regard to a subsequent nonprovisional application.
Because the provisional is not reviewed in this manner, there is no back-and-forth with the examiner during which alternations can be made.
- You would have to file a subsequent provisional patent to introduce changes
This may be useful for additions, but you don't need to do so for subtractions, as you can simply omit the latter material in a subsequent nonprovisional application.
Assuming you are applying for a utility patent, then you shouldn't be limiting the claims to exactly one configuration. Instead of say 10 slots, the claim language should read something like "a plurality of slots...". Its important when applying for a utility patent to very clearly understand what the actual invention is and to try to claim it as broadly as the patent office will allow. A qualified patent attorney or agent is extremely valuable in this regard.