Google "Huawei Nortel Networks". The fact is that Nortel has an enormous volume of R&D stolen from them and the allegation is that Chinese telecom providers were the main beneficiaries.
Edited: To reply to a child post, this is about the allegations referred to in the parent, not a statement of what I think is true now
Edited: To reply to a child post, this is about the allegations referred to in the parent, not a statement of what I think is true now