Big corps that use OSM are actually contributing a lot back into OSM by actually fixing data issues. I have seen that first-hand; at a Corp that was using OSM, they had a big team doing just that the whole working day. Just fixing issues in OSM that the customer have reported.
I think they in the end decided to fork OSM and make it proprietary to keep the data in-house; but I might be wrong. I was not there anymore.
edit: maybe I am wrong. It was Grab, "uber for Asia". They still edit OSM it seems...
https://wiki.openstreetmap.org/wiki/Grab#Grab_Data_Team
edit2: the users seem to be inactive now, so maybe I was right. I don't know.
edit3: when I look at the corporate members, lots of them seem to be taxi companies. I guess it makes sense. I see Gojek, Grab and Bolt.