If we assume for a moment that the IETF Trust were to own the IANA trademarks, significant issues arise.

In a trademark license, the IETF Trust, as licensor, would have the power to terminate the license according to its terms (e.g., for material breach of the agreement, misuse of the trademark, etc.) or to decide not to renew the license, in which case ICANN would no longer have the right to use the IANA trademark in the provision of services.  It would be inappropriate for the IETF Trust to have this power, without accountability to and oversight by the names and numbers communities.  A mechanism would need to built for that.  

Quality control presents another challenge.  In virtually all circumstances, a licensor exercises these quality control obligations through an employee or employees knowledgeable and capable of exercising quality control over the licensee and its services.  .It may also be appropriate for the operational communities to be involved in quality control and other aspects of the license as well, especially since quality control and trademark usage guidelines can be changed from time to time, typically at the licensor’s discretion, and since the IETF is not in a position to exercise quality control in the names and numbers space.  This may require amendment of the IETF Trust Agreement, as well as the drafting of a somewhat unusual trademark license.

Furthermore, the IETF Trust would also be responsible for policing and enforcement of the trademark against third parties and for maintenance of trademark registrations.  

It is not clear how the IETF Trust intends to carry out any of these roles.

Also, for the IETF Trust to become the owner of the IANA trademark, ICANN would need to assign all of its right, title and interest in and to the IANA trademark to the IETF Trust, along with all goodwill relating to the mark (typically, in exchange for good and valuable consideration).  This may require a valuation of the IANA trademark and its associated goodwill, which in turn may have tax or other financial consequences for one or both parties. 

Finally, the IETF Trust, as such, may not  be capable of owning the IANA Trademark, since the IETF Trust does not appear to be a “legal entity.”  If this is correct, the Trustees (in their role as Trustees) are the collective owners of the IANA Trademark (in trust for the IETF, as Beneficiaries of the IETF Trust), and would need to enter into the trademark license (again, in their role as Trustees of the Trust).  This appears to be consistent with Section 9.5 of the Amended and Restated Trust Agreement and the ownership of the IETF trademarks (which are owned by “The Trustees of the IETF Trust”) in the USPTO database.  (Oddly, this is inconsistent with the IETF General Trademark License (on the IETF Trust website) which states that the IETF Trust is the licensor of the IETF marks, and which also lacks appropriate quality control provisions.) 

Greg Shatan