I hope he’s paying his estimated tax on that...
I doubt he will have to pay any taxes on the proceeds if it a gift. His lawyers will make sure it is structured tax free. At $250K and climbing I would expect some level of IRS scrutiny.
I can walk up to a stranger on the street and give them a big amount of money tax free as long as it doesn't exceed $14K. At $14K the giver is responsible for any gift taxes. Now if the giver expects services to be performed at a later date, it would be income and both would have to comply with the IRS laws.