Bearing in mind the notion of trade-off it is not reasonable to ignore SGPS´s disadvantages, as well as, do not to forget the analysis dimensions: corporate income and selo tax (IS).
Regarding dividends and/or similar (capital and interest gains), if equity shares acquisition resumes a period less than one year with capital losses, tax deduction is not possible. And, such is incurred to financial costs bond to acquisition process. Referring interest gains, the exemption for withhold tax on additional capital contracts, depends on one-year term (cross-sectional and sine qua none assumption); and, less than 10% of the voting capital.
Finally, in corporate income analysis, to create a SGPS or similar to fully aggregate a group of companies consider the Regime Especial de Tributação dos Grupos de Sociedades (RETGS). This regime enables an immediate compensation of profit and loss in each financial year; and, dismisses tax withholding on payments between entities.
The only problem in IS derives from the time factor in cash shortfall operations, ie, if the legal limit of one year is exceeded in such operations (descendants and ascendants) these are subject to tax.
Concluding, SGPS´s have vital tax advantages for economic groups growth (either organic or by acquisition). However, time constraints pressure financial costs deduction (debt management) and capital losses on divestitures (cash management).