The concerns spawned from the companies’ sales of electronic products online.
“(Restrictions) would affect the retail sale of Apple products by third parties and the advertising of competing Apple products, leading to a reduced competition in the internet retail market for electronic products,” the CNMC said.
The CNMC also might strengthen Amazon’s position of providing marketing services for third-party retailers via online platforms in the country.
CNMC proceedings are open for a maximum of 18 months, for the investigation and resolution of the case.
Amazon has said it is fully cooperating with the investigation.
The big tech firms have caught flak in recent months. In another investigation, the German antitrust regulator has been looking into Apple for competition law regulations.
The Bundeskartellamt announced the probe earlier this year, and it was the fourth investigation into a large digital firm, after cases looking into Facebook, Amazon and Google before.
The cases all came from the new amendment to the German Competition Act, which let the authority have power to intervene more in cases of big tech companies.
The company said it was looking into whether Apple was engaging in anti-competitive actions, including its reported restrictions of user-tracking and prioritizing its own apps over others.
There was also the six-bill package debated recently by the U.S. House which would help to stop the dominance of these big tech companies.
The bills were proposed because of a report in April which found a need for changes to antitrust law.