Anyway, why these transactions?
Might be somebody who is really pissed or bored and is sending dust to that address.
Happened with the silk road seized coins address also:
https://blockchain.info/address/1F1tAaz5x1HUXrCNLbtMDqcw6o5GNn4xqX?offset=0&filter=0
Basically they send 1$ worth of coins hoping it will cost MtGox 10$ to move the coins.
But with the empty mempool it makes no sense nowadays.
It's nothing new, all the addresses in the top richest are receiving this ....treatment.
Look at the other posts above... there are a bunch of transactions of 10,000 BTC which are recent, a 20,000BTC one, some 1 BTC ones, and some worth around $100 bucks which is too much to annoy anyone, specially now that the mempool is empty.
Hell, even these $10 worth transactions could be moved easily, they aren't doing nothing but making whoever controls the MtGox address now even richer... doesn't make sense to me.
My reply was exactly for the part I've quoted in my answer, and only about the small transactions.
And there are plenty of those
As for the other question....
How do we know this address belongs to MtGox?
http://coindata.info/mtgox.php
It certainly isn't mentioned here, there are no google search result for it with MtGox and on reddit people claim it's actually Bittrex....
Well im not exactly sure how that is the address that belongs to Mt.Gox, but it's pointed out by several OG's in twitter that that is indeed the address from Mt.Gox:
https://twitter.com/matt_odell/status/972193512849584129
It's also all over reddit. I know reddit is a joke but someone should have pointed out at this information being false already. I think this is the real deal and these coins are from Mt.Gox, so we have someone funding this address for some unknown reason. I haven't heard any convincing arguments as to why that money is moving in yet.