You're speaking to the issue of what are called extended continental shelves. Under article 76 of the United Nations Convention on the Law of the Sea, a coastal state can be recognized as having sovereign rights over the seabed only, beyond 200 nautical miles, if it can demonstrate that the seabed is a natural prolongation of its land mass.
As it happens, North America and Eurasia used to be a single continent. Russian and Canadian and Danish scientists believe that the Lomonosov Ridge is a natural prolongation of both sides, which is why in 2014 Denmark submitted scientific data to the United Nations showing that the Lomonosov Ridge was an extension of Greenland all the way across to the Russian exclusive economic zone, to 200 nautical miles from Russia.
Russia responded with its own submission in 2016, where it argued scientifically that the ridge was a prolongation of the Eurasian continent but quite remarkably did not extend its submission all the way across. It actually stopped roughly two-thirds of the way across.
I asked one of the Russian diplomats involved as to why they had done so, and they pointed out that all of the Arctic countries agree that there will be overlaps in our submissions and that those submissions are only about the science. The overlaps will have to be negotiated into boundaries through diplomacy.
If you go back to read Alan Kessel's testimony to this committee, that's exactly what he was talking about.
There has been a lot of misinformation on this from the media, because it is highly technical. However, it is an area where Russia is following the rules, and Canada has been working very hard with Russia to ensure consistency and collaboration on this matter.