From Power Engineering:
The second largest oil and gas company in the U.S. is putting some of
 its venture capital into a start-up focused on advanced modular nuclear
 reactor technology.
Chevron Corp. announced a Series A investment in Seattle-based Zap 
Energy. Zap is working to develop a plan on advancing commercially 
scalable nuclear fusion reactors.
Chevron is one of the world’s 10
biggest oil companies and second in the U.S. only to ExxonMobil.
This investment marks the 10th
investment by Chevron’s Future Energy Fund, which was launched in 2018 to
explore breakthrough technologies that enable macro decarbonization, the
mobility-energy nexus, and energy decentralization.
“We see fusion technology as a
promising low-carbon future energy source,” said Barbara Burger, president of
Chevron Technology Ventures....MORE
Italy's ENI has invested in a couple different projects, here's Nuclear Engineering in 2018: 
Italian oil and gas company Eni on 4 May signed a memorandum of 
understanding with the National Research Council (CNR) covering joint 
research in nuclear fusion, water, agriculture and the Arctic ecosystem.
 Eni and CNR are to invest more than €20m ($28m) over five years to 
establish a fusion research centre in Gela, Sicily - one of four joint 
research centres to be set up under the agreement. 
“This agreement
 represents a significant step forward for Eni towards the development 
and implementation of increasingly efficient technologies capable of 
creating sustainable and accessible energy for more and more people", 
stated Eni CEO Claudio Descalzi. He added that Eni has long been 
committed to supporting scientific research for the realisation of 
concrete and scientifically sound solutions to support the 
diversification of the energy mix towards increasingly sustainable 
sources. Joint working groups will be set up to define the operation of 
the centres, the projects to be launched in the coming five years, the 
distribution of resources, and to draw up a cooperation agreement for 
joint management of the centres. Joint strategic workshops will be 
organised. The first will be held in September. 
Earlier Eni said 
it was considering stepping up its investment in nuclear fusion. The 
company is already involved in a collaboration the US Massachusetts 
Institute of Technology (MIT), which has set up a new private company, 
Commonwealth Fusion Systems (CFS), in which Eni has shares. CFS in 
April, announced an initial investment of $30m to develop a fusion 
reactor prototype within 15 years, after which Eni’s head of development
 operations and technology, Roberto Casula, said Eni might increase its 
investment in the project...MORE
And 
Norway's Equinor is also invested in Commonwealth, along with the Breakthrough Energy Ventures fund (Bill Gates, Jeff Bezos and others)