Question juridique clé
Whether the AHV contribution assessment had to follow the direct federal tax assessment for 2007.
Solution extraite
The direct federal tax assessment was not binding for AHV purposes because, as to self-employment income, it was manifestly incorrect.
Motifs extraits
The tax authorities had reported a total income, but the available circumstances made it impossible that the appellant earned CHF 40,000 from self-employed massage work between September and December 2007; therefore the social insurance authority had to reassess the contribution basis itself.