Yep the big three plus Huawei with a bit of an edge on them with te standard essential patent , that they collaborate in a pool with.Although in the matter of mobile modems/radios Qualcomm has an edge over all the others - not so much in the backend/longhaul telco space. Additionally if i recall most of the 6G stuff is being pushed by Huawei since most of it rests on the current 5G/5G+ work.

I get that they are now involved and contribute to 5g. But its pretty shameful how huawei had acquired the ability to do so.

https://en.wikipedia.org/wiki/Concerns_over_Chinese_involvem...

https://www.bloomberg.com/news/features/2020-07-01/did-china...

https://www.politico.com/news/2020/02/13/us-charges-huawei-w...

These are articles are basically all speculation with no solid evidence.

Nortel was dying way before Huawei got involved.