The first and most important thing to note about the consequences of backdating a document is that it is potentially a criminal offence.
This is important to note, because the grant date is what determines the exercise price on the options.
Additionally, companies can use backdating to produce greater executive incomes without having to report higher expenses to their shareholders, which can lower company earnings and/or cause the company to fall short of earnings predictions and public expectations.
Corporations, however, have defended the practice of stock option backdating with their legal right to issue options that are already in the money as they see fit, as well as the frequent occurrence in which a lengthy approval process is required.
Those options give John the right but not the on the date of the grant.
The board formally grants the stock options to John every year at its January board meeting.