Nope. It is (was) part of the E. B. Eddy forest access road network which had the cutting rights for the area. All of that is now in the hands of Domtar. The main east-west road is now known as the Sultan Industrial Road but there are a network of feeder roads as well as offshoot roads that connect Biscotasing and Ramsey (both on the CP) as well down to Hwy 17 and the pulp mill in Espanola.
It's been years since I've been on it. It did cut a fair bit of time off the normal route through the Soo, but there were several caveats. How well it, or any of the roads in the area were maintained depended on how much the company and its contractors were using it and if you were on a not-maintained section it was just washboard and dust. Back then, there was a sign at both ends stating that, although public access was permitted, the company accepted no liability and the vehicles did not have to meet highway standards. This usually meant that they were over-width and over-length. The haul drivers were mostly, not to put too fine a point on it, nuts.
I vaguely recall there was some kind of provincial funding even back then but don't know how much that has changed and if it changed the road's status. It is now a secondary highway from Hwy 129 to Dalton, although I believe that stretch was always a public road.
There has always been some level of lobbying for it to be brought up to a public road standard, equally fought by SSM and the towns along the Hwy 17 corridor. In my mind, that would create some knock-on impacts. In addition to the cost of upgrading the road to some kind of standard, Hwy 101 goes through the town of Wawa, and Hwy 144 goes through a lot of built-up area in northern Greater Sudbury. Even though they are King's Highways, 101, 129 and 144 are not built to same standards of 11 and 17. There are also very few communities and virtually no services on those stretches of 101, 129 and 144 (more on 144 as you get into Greater Sudbury) and no hydro, telecoms, etc. for much of the route.