During the pendency of the application for registration, it is possible to assign the trademark application to a third party. The assignment is valid in respect of third parties when the assignment agreement is filed before INAPI and it is recorded in the Registry.
The assignment should at least be in writing and in a single document signed  before a notary between the assignor and the assignee.

Consequently, the only requirement to assign an application is that the trademark application is pending, having as deadline to file the document the final day to pay and prove the payment of the registration fee, if the trademark has been accepted.
If the assignment agreement is submitted after a trademark is granted, it is necessary to assign a trademark  registration, paying a fee of 1 UTM.