Back before the SEGA and Sammy merger, Sammy published a pretty good fighting game known as Guilty Gear. The games where developed by Arc System Works. When the merger happened, the rights to the series were owned by SEGA Sammy. Sadly SEGA Sammy had no plans to continue the franchise.
Arc System Works started a new 2D fighter for this generation called Blazblue. Hardcore fighting fans never forgot their original franchise and asked if it would ever come back. Daisuke Ishiwatari, creator of Guilty Gear, said there would be a new game eventually.
Now Arc System Works filed a trademark for “Guilty Gear”, which was published in the Japanese database today. This either means that the developer bought the rights to the franchise from SEGA-Sammy or SEGA-Sammy gave them the franchise. Most likely bought.
Arc System Works has confirmed that they do own the Guilty Gear franchise now, so this isn’t some sly deal.