TENARIS S.A. ANNUAL

Business / Consolidation

B Group accounting (1) Subsidiaries and transactions with non-controlling interests Subsidiaries are all entities over which Tenaris has control. Tenaris controls an entity when it is exposed to, or has rights to, variable returns from its involvement with the entity and has the ability to affect those returns through its power over the entity. In some cases, the Company considers that it has the ability to affect returns through its power over an entity even if it holds less than 50% of the shares or voting rights of the subsidiary because it is able to prevail at all of the subsidiary’s general meetings, which in turn allows Tenaris to nominate and appoint a majority of the subsidiary’s board of directors. Subsidiaries are fully consolidated from the date on which control is exercised by the Company and are no longer consolidated from the date control ceases. The acquisition method is used to account for the acquisition of subsidiaries by Tenaris. The cost of an acquisition is measured as the fair value of the assets transferred, equity instruments issued and liabilities incurred or assumed at the date of exchange. Acquisition-related costs are expensed as incurred. Identifiable assets acquired, liabilities and contingent liabilities assumed in a business combination are generally measured initially at their fair values at the acquisition date. Any non-controlling interest in the acquiree is measured either at fair value or at the non- controlling interest’s proportionate share of the acquiree’s net identifiable assets. The excess of the aggregate of the consideration transferred and the amount of any non-controlling interest in the acquiree over the fair value of the identifiable net assets acquired is recorded as goodwill. If this is less than the fair value of the net assets of the subsidiary acquired, the difference is recognized directly in the Consolidated Income Statement. Contingent consideration is classified either as equity or as a financial liability. Amounts classified as a financial liability are subsequently remeasured to fair value with changes in fair value recognized in profit or loss. If the business combination is achieved in stages, the acquisition date carrying value of the acquirer’s previously held equity interest in the acquiree is remeasured to fair value at the acquisition date. Any gains or losses arising from such remeasurement