PurposeThe present study investigates the connection between company investments in intellectual capital (IC) and how they translate into financial value. The aim is to test the impact of intangible assets on the firm value and its sustainable growth.Design/methodology/approachThe research employs computation models to determine the sustainable growth rate (SGR) and the firm value (FV), and by using the ordinary least squares (OLS) model through a linear regression assesses the relationship between the dependent variables and expenditures on intangibles like R&D, IT programs and patents. A sample of 42 companies has been selected out of the 78 listed at Bucharest Stock Exchange (BSE), based on the appropriateness of the information disclosed in the financial reports for the period 2016–2019.FindingsThe results show that intangibles classified as innovative competences (R&D and Patents) do not have a positive impact on SGR and FV in listed companies from Romania. Moreover, R&D has a negative and significant effect on FV, while IT Programs have a positive and significant impact on FV, but not on the SGR. Variables categorised as economic competencies (Brands, Shares held in associates and jointly controlled entities) and firm structure-specific variables (Leverage, Firm Performance) seem to have a significant effect on SGR and FV. Shares held in associates and jointly controlled entities is the variable that can have the biggest impact when it comes to FV for companies listed at BSE.Research limitations/implicationsDue to non-disclosure of specific information by some companies, or lack of investments in intangibles the sample had to be reduced and does not cover all listed companies.Practical implicationsCompanies listed on the Regulated Market from the Bucharest Stock Exchange should maintain their scale of liabilities at a reasonable level when financing intangible assets in order to ensure corporate long-term and sustainable development. Also, these companies should maintain awareness about the importance of intangible assets and invest more in specific sub-components, in order to sustain competitive advantage. Recognizing the roles of intangibles, managers need to develop strategies to invest in profitable intangibles by reasonably allocating their limited resources, in order to achieve sustainable growth and increase company success.Originality/valueStudies concerning the relation between investments in intangibles and sustainable growth rate and firm value of listed Romanian companies are very scarce. This paper reveals new research, never before undertaken, concerning expenditures on intangibles by Romanian companies and the valuation of such investments on Bucharest Stock Exchange.