Morning Boys -
Mr. Kennedy is correct that the possibility of the benefit of future royalties is "other valuable consideration".
And there have been instances (quite rare, thankfully) where sheister companies have tried to claim that that and other possible future benefits constituted valid consideration, and that that was acknowledged as received and sufficient in the wording of the lease.
If I remember correctly, a lease brokerage outfit here in the Barnett Shale area of North Texas tried that stunt a few years ago when their client company suddenly dropped the prospect they had been working on and refused to send them the funds to honor the drafts they had issued.
Thankfully, Judges are not typically stupid people.
Having said that, however, I should also point out that a Lessor knowingly giving a Lessee a "free lease" is not entirely unheard of either. The "promise" to drill a well within a certain number of days or months or something similar to that being the moving consideration of the lease.
You have to have a moving consideration or no transaction is valid.
Mr. Mullins, you reminded me of something that I haven't thought of for a while. There is no need to pay an escrow service:
Prior to about the early 1970's, all original signed Leases were submitted to the Lessor's bank [Your bank's Collections Department] along with the Draft issued for the Bonus Payment. When the draft was honored by the Lessee's bank, the Lessor's bank would forward the lease to the Lessee.
You are still perfectly welcome to do it that way, and thus will be completely protected.
Your Bank will charge you $50 - $75 for the service, which the Lessee might be willing to pick up the tab on - especially when the draft is for only a small amount of money.
Either that or you can request a cash item, such as a check or cashier's check.
Hope this helps -