"protect our brand." They wanted 'Scrolls' too.
ZeniMax, parent of Bethesda, own The Elder Scrolls and weren't happy. Notch claims they "offered both to change" or drop the trademark; "Bethesda refused on both counts."
"We realized we should apply for the trademark “Minecraft” to protect our brand. When doing so, we also sent in an application for “Scrolls”. When Bethesda contacted us, we offered both to change the name to “Scrolls:
"They refused on both counts."
"Whatever reason they have for suing us, it’s not a fear of us having a trademark on the word “Scrolls”, as we’ve offered to give that up." Minecraft's creator revealed this information to "clarify a couple of things" after published an article on the debacle.
The gist appears to be that Mojang got a little greedy with the 'Scrolls' trademark, effectively trying to own the word in all forms of media, to which ZeniMax took immediate offense because of their The Elder Scrolls franchise which would be affected.
ZeniMax and Mojang are due in court where the Bethesda owner claims Mojang's card game would potentially confuse people between it and the Elder Scrolls RPG series.