One of the most difficult standard phrases to interpret once the issue arises is when a party´s consent or approval is required but not to be unreasonably withheld, conditioned or delayed. This is a species of the standard of reasonableness. In most ordinary course contracts, the phrase is inserted to avoid lengthy discussion or an elaboration of unknown (but for those who like creative brainstorming, foreseeable) events that could be addressed.
Example. The phrase is typically used in assignment clauses:
No Party may assign rights or obligations of this Agreement without the consent of the other Party, which consent shall not unreasonably be withheld or delayed.
The difficulty is that a party being asked to consent to such assignment can potentially leverage its bargaining power to settle pending claims or uncertainties or even to prevent an assignment taking place by raising ´reasonable´ objections. Such objections could include the requirement to be informed about specific consequences of such assignment. It must be considered that not unreasonably be withheld or delayed results in some negotiation or the creation of certainty of payment or timely performance by the assignee.