Softbank Group Chief Operating Officer Marcelo Claure said it is "business at usual" at the companies backed by its almost $100 billion Vision Fund despite a tense situation with Saudi Arabia, which provided almost half of the fund's capital.
Turkish officials say they fear Saudi agents killed Khashoggi after he entered the Saudi Consulate in Istanbul on October 2.
But it's also bad news for SoftBank (sftby), the Japanese conglomerate that has close ties with Saudi Arabia.
SoftBank stock was down nearly 8 per cent in early afternoon trade.
The Foreign Ministers of the United Kingdom, France and Germany on Sunday expressed serious concerns about the fate of a missing Saudi Arabian journalist and called for an investigation into the case.More news: Mysterious polio-like illness baffles medical experts while frightening parents
Under Son, SoftBank built its global influence through tech investments and raised over $93 billion previous year to create its Vision Fund - with $45 billion coming from Saudi Arabia.
In response, executives at some major US companies announced they would no longer attend the "Davos in the Desert" conference hosted by the country.
Masayoshi Son used Saudi Arabia's oil riches to help him become one of the world's most powerful tech investors.
JPMorgan chief executive officer Jamie Dimon, Uber Technologies' Dara Khosrowshahi and Viacom Inc's Bob Bakish are among those who have dropped out of attending the conference.
SoftBank Group Corp shares tumbled 5.5 per cent on Monday, hurt by worries over its ties to Saudi Arabia as well as a broader market sell-off.
Saudi Arabia's Future Investment Initiative, which has been nicknamed "Davos in the Desert", is due to start on Oct 23 and bills itself as "a blueprint for the 22nd century". SoftBank and Saudi Arabia said in March they would build the world's biggest solar power generation project. And it's a move he plans to repeat: earlier this month, it was reported that the Saudis were prepared to put another $45 billion into a second Vision Fund, using cash from the planned stock market flotation of state oil firm Saudi Aramco and the sale of a stake in the Saudi manufacturing giant SABIC (sabic).