water leaking into neighbors house

[zappacosta]

I live in a semi detached home. My niegbor recently had his house waterproofed and all was ok for a awhile, however my basement started leaking earlier this year from the outside window and he claims that some of this water has found its way into his house. I have sealed the window where i believe my water was entering and the leak stopped for now and for good i hope. HOwever this neighbor has threatned me with legal action if water gets into his house becasue i havent done the same waterproofing he did, ie dig to the footing, tar it up and all that jazz. I told him to shut up and look after his own property becasue this is his problem and has nothing to do with me, am i right?