Trademark Office approval not required before using ITU mark
There is no legal requirement to wait for USPTO approval of your Intent-To-Use application before you can begin using the mark. If you have started using the mark on all the goods or services in your ITU application, you can file an Amendment to Allege Use (AAU) prior to the time your application is published for opposition.
Filing an acceptable AAU during an earlier stage of your ITU application may speed up the registration because you will by pass the Notice of Allowance which would normally trigger a 6-month deadline for filing use evidence. Assuming no one opposes your mark and your use evidence is acceptable, your application will proceed to registration sooner.
Should you wait for USPTO approval before commencing use of your intent-to-use mark?
If you would prefer to see if your ITU application will be approved before commencing use, then it may be advisable to wait for an initial determination by the USPTO trademark examiner (i.e., examining attorney). It could take 3-6 months to receive an indication as to whether your mark may be refused.
Even if the trademark examining attorney approves your application, it is not a guarantee that your mark will register. Third parties will have an opportunity to oppose your application.
Filing multiple ITU applications concurrently for different marks
If you’re contemplating a few different names for your product and you can afford to wait a few months, then one strategy may be to file concurrent ITU applications for different marks. You then wait to see which marks will get rejected versus those that get approved.
Before filing, however, conduct knockout searches for any highly similar marks already filed with the USPTO. An experienced trademark attorney can provide counsel on not only searches, but also on any descriptiveness refusals you may encounter with marks that are too descriptive of your goods or services.