This research analyses the significance of human asset specificity (HAS), physical asset specificity (PAS), and investment collaboration (IC) in Indonesia’s offshore companies, affecting the business performance through mediator variables. Implementing theory of transaction cost economic (TCE) and relational view to examine these interactions; some hypotheses are constructed, regarding contractual governance (CG), and relational governance (RG) as a mediating variable. The research applies partial least square-structural equation modelling (PLS-SEM) to analyse data sample that comprises 159 offshore companies in Indonesia. The study analyses how HAS, PAS, and IC on business performance is influenced by CG and RG. The study strengthens the literature on HAS, PAS and IC by theoretically exposing and empirically enlightening how CG and RG collaborating effect a positive relation among HAS, PAS, IC, and business performance. Copyright © 2023 Inderscience Enterprises Ltd.