It's occurred to me that buying the rights to the Aragon drug might be an excellent negotiating ploy for JNJ. They must know that Zytiga will eventually be replaced by Xtandi. If they want to spend a lot of time and money in court in addition to the time and money involved in running trials, they may prevail. Or not. By which time MDVN may have themselves developed a more effective analogue of Xtandi. If they were to pay $7 billion for MDVN ( = roughly $90 a share), the $1 billion they spent on Aragon would be a cheap price to remove the uncertainty and have a complete lock on the molecule.