• Renewal Fees must be paid for some IPRs
• Attempts by competitors to have the IPRs revoked may have to be repulsed

Obviously letting a patent or other IP lapse due to failure to pay renewal fees or failing to defend attempts to revoke the patent might save the licensor money in the short term. It would however be to the detriment of the licensee who may have invested large sums of money on the assumption that IP protection would continue. Courts may imply into the terms of a licence the need for a licensor to pay renewal fees and keep patents in force but it is better to have explicit terms to ensure that the IP is preserved and protected from attack or lapsing.

Trade Marks
If there are trade marks involved in the licence the licensor will want to include terms protecting the manner in which the trade marks are used by the licensor in order to preserve the trade marks for future use by the licensor or so as not to harm the reputation of the licensor. Maintaining the quality of the licensee's goods can be critical in this respect.

"No Challenge' clauses
The licensor may want to prevent the licensee from challenging the validity of the IP concerned in order to avoid paying the royalities due to the licensor. Such a ban may be implied by courts in any event.

Under EC regulation 773/2004 any direct or indirect obligation on the licensee not to challenge the validity of intellectual property rights held by the licensor in the common market is not block exempted though it will not preclude the whole agreement from exemption. However, the regulation does cover the possibility for the licensor to terminate the licence agreement if the licensee challenges the validity of the licensed technology.