The article isn't clear but could it be that Summly has a licensing deal with SRI for their "summarisation technology" and Yahoo wants to take full ownership of that "summarisation technology" and the licensing deal Summly has means that's not possible for Yahoo to do? For example Summly could have the only (maybe exclusive?) 5 year license on whatever... so Summly is acquired by Yahoo and now Yahoo has the only license and full ownership?

Would Yahoo acquiring the licensed SRI technology allow them to void any existing licenses?