How exactly did Penders win over Archie and Sega. It boggles the mind how he could claim ownership and actually succeed when he was a hired talent writing for an existing property.
My understanding is this:
When Archie staffed up for the Sonic comic, nobody ever drew up proper "Work for hire" contracts. A "Work for Hire" contract usually states that anything made while employed by that company becomes their property. Meaning if Archie had those contracts in order, anything Ken Penders made while working for Archie would be the property of Archie Comics Inc. or whatever.
Since they didn't do that, once Ken Penders was fired from Archie Comics (2006 or so), he eventually realized that "nobody" owned the Sonic Comic characters he created while working for them. Since those characters are literally the most successful thing he's ever done, he went ahead and filed trademarks and copyrights for all of them so that he owned them outright.
The way Ken Penders tells the story, Archie was notified about him doing this, but didn't stop him.
Ken eventually announces he has plans to use these characters in an upcoming graphic novel he's writing. Archie Comics catches wind of this and says "No, those are our characters, you can't do that." and Ken's like "Nuh-uh, I own them legally."
So Archie sues Ken over it, and Ken sues Archie back.
Both sides dragged their feet on their respective lawsuits for SO LONG that the Judge visibly became angry with them for not having enough evidence for either side of the suits. He gave them deadlines to get their shit together or else he'd dismiss everything. It was basically the most polite, legally correct version of "Both of you can fuck off."
It's been a long time, but I believe one case WAS dismissed, but Archie Comics settled on the rest. The terms of the settlement have never been made public.
While all of this was going on, the Sonic comic rebooted several times. Once just to get rid of all the dangling plot threads Ken Penders left behind after being fired, and then once to get rid of Ken's characters, and then once more to get rid of ANYTHING that might be objectionable.
That's because, during all of this stuff, Ken Penders publicly said that if any other people who worked at Archie wanted to follow in his footsteps and claim their characters, he'd be glad to help them out. It really made him sound bitter and vindictive. No longer was this about him figuring out a loophole Archie accidentally left open and exploiting it for his own gain, now it was starting to look like he was out to burn Archie Comics to the ground -- or at least the Sonic portion of it.
Only one other person has ever come forward so far: Scott Fulop, who tried to trademark a handful of minor characters, got in to the same legal battles as Ken Penders, and then tried to back out. Reportedly, Archie denied him from backing out of their lawsuit, and that's the last I heard of the Scott Fulop situation. I think they're trying to hold his feet to the fire.
Ken, meanwhile, revealed that his shitty Knuckles characters were intended for more than just graphic novels. He wants movies and books and whatever else he thinks he can get away with. He's furiously counting chickens before they hatch even as we speak.
Sega was rumored to be very angry with Archie Comics that they let Ken Penders get as far as he did. Undoubtedly that was part of all this -- rumor has it that Sega was upping the licensing fees for Archie, and Archie isn't in the best financial situation right now. Supposedly they want to simplify their output back to just doing Riverdale stories again and with them pushing the TV series so hard and rebooting all of their Archie stuff recently that definitely looks like the case. Archie Comics doesn't want to do Sonic anymore, and Sega is asking for too much money for them to justify the cause, even if Sonic was still one of their top sellers.