WormBase curates four different types of gene-to-gene interaction data: genetic, regulatory, physical, and predicted. These data are found in the interactions widget in each gene page. Aside from the predicted interactions, the other three types are curated with direct experimental evidence from the literature. Check out the micropublication which describes the Vennter tool. This tool is integrated into the interactions widget on WormBase gene pages and allows the visualization and analyses of interaction data.
If you are looking for interaction data for C. elegans look no further than our FTP site. At every release WormBase deposits data files on the FTP site under the relevant release number and species directories. The files are named after the data they contain. The interactions file for C. elegans for the WS261 release can be found here and is called c_elegans.PRJNA13758.WS261.interactions.txt.gz