Kernrechtsfrage
Whether a voluntary buy-in into a pension fund by a self-employed person is deductible for AHV contribution purposes only if it is mandatorily prescribed by the pension rules.
Extrahierter Entscheid
A self-employed person may deduct from contributory income not only mandatory but also voluntarily made buy-ins, provided the pension scheme's statutes or regulations allow the buy-in; a mandatory prescription is not required.
Extrahierte Begründung
The court held that Art. 9(2)(e) AHVG, read with Art. 18(1) AHVV, does not justify importing a requirement that the buy-in be obligatory. Such a requirement would be systemically inconsistent for self-employed persons, for whom occupational pension participation is voluntary. The tax-law analogy supports deductibility of permitted buy-ins, subject to the AHV-specific cap that only half of the amount is deductible.