That appears to be the case here, too. WordPress can’t try the relicensing move. It’s licensed under the General Public License version 2 (GPLv2), This license is both irrevocable and requires any derived work to be licensed under the same license. What Mullenweg can and is doing, though, is trying to shake down WP Engine for more money.
As my fellow journalist Matthew Ingram pointed out in an excellent essay on the conflict, “Matt is not just the plucky founder of a nonprofit open-source project, he’s a wealthy CEO of a for-profit corporation that is attacking a competitor, and using his status as the founder of the nonprofit to extract money from that competitor.”
From where I sit, this is not a battle over open source. It’s a fight between someone worth hundreds of millions and a company worth billions. When you’re trying to figure out what’s going on in any conflict, whether it’s a family fight, a divorce, or a business fight, one of the best rules of thumb is to follow the money. What it’s telling me here is it’s about the cash.